diff --git a/api/src/channel/lib/Handler.ts b/api/src/channel/lib/Handler.ts
index c454b365..f797537d 100644
--- a/api/src/channel/lib/Handler.ts
+++ b/api/src/channel/lib/Handler.ts
@@ -214,7 +214,7 @@ export default abstract class ChannelHandler<
     envelope: StdOutgoingEnvelope,
     options: any,
     context: any,
-  ): Promise<{ mid: string }>;
+  ): Promise<{ mid: string | string[] }>;
 
   /**
    * Calls the channel handler to fetch attachments and stores them
diff --git a/api/src/chat/controllers/message.controller.spec.ts b/api/src/chat/controllers/message.controller.spec.ts
index 0bc9e2a5..92a4787a 100644
--- a/api/src/chat/controllers/message.controller.spec.ts
+++ b/api/src/chat/controllers/message.controller.spec.ts
@@ -144,6 +144,10 @@ describe('MessageController', () => {
 
   afterAll(closeInMongodConnection);
 
+  function toArray(value?: string | string[]): string[] {
+    return value ? (Array.isArray(value) ? value : [value]) : [];
+  }
+
   describe('count', () => {
     it('should count messages', async () => {
       jest.spyOn(messageService, 'count');
@@ -165,8 +169,13 @@ describe('MessageController', () => {
       expect(messageService.findOneAndPopulate).toHaveBeenCalledWith(
         message.id,
       );
+      const expectedFixture = messageFixtures.find(
+        ({ mid }) =>
+          JSON.stringify(toArray(mid)) === JSON.stringify(message.mid),
+      );
       expect(result).toEqualPayload({
-        ...messageFixtures.find(({ mid }) => mid === message.mid),
+        ...expectedFixture,
+        mid: toArray(expectedFixture?.mid),
         sender,
         recipient,
         sentBy: user.id,
@@ -177,8 +186,13 @@ describe('MessageController', () => {
       const result = await messageController.findOne(message.id, []);
 
       expect(messageService.findOne).toHaveBeenCalledWith(message.id);
+      const expectedFixture = messageFixtures.find(
+        ({ mid }) =>
+          JSON.stringify(toArray(mid)) === JSON.stringify(message.mid),
+      );
       expect(result).toEqualPayload({
-        ...messageFixtures.find(({ mid }) => mid === message.mid),
+        ...expectedFixture,
+        mid: toArray(expectedFixture?.mid),
         sender: sender.id,
         recipient: recipient.id,
         sentBy: user.id,
diff --git a/api/src/chat/dto/message.dto.ts b/api/src/chat/dto/message.dto.ts
index a5855bde..3e1b6e14 100644
--- a/api/src/chat/dto/message.dto.ts
+++ b/api/src/chat/dto/message.dto.ts
@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Hexastack. All rights reserved.
+ * Copyright © 2025 Hexastack. All rights reserved.
  *
  * Licensed under the GNU Affero General Public License v3.0 (AGPLv3) with the following additional terms:
  * 1. The name "Hexabot" is a trademark of Hexastack. You may not use this name in derivative works without express written permission.
@@ -11,8 +11,8 @@ import {
   IsBoolean,
   IsNotEmpty,
   IsObject,
-  IsString,
   IsOptional,
+  IsString,
 } from 'class-validator';
 
 import { IsObjectId } from '@/utils/validation-rules/is-object-id';
@@ -27,7 +27,7 @@ export class MessageCreateDto {
   @ApiProperty({ description: 'Message id', type: String })
   @IsOptional()
   @IsString()
-  mid?: string;
+  mid?: string | string[];
 
   @ApiProperty({ description: 'Reply to Message id', type: String })
   @IsOptional()
diff --git a/api/src/chat/repositories/message.repository.spec.ts b/api/src/chat/repositories/message.repository.spec.ts
index 784df2cd..10cc1b7e 100644
--- a/api/src/chat/repositories/message.repository.spec.ts
+++ b/api/src/chat/repositories/message.repository.spec.ts
@@ -56,7 +56,11 @@ describe('MessageRepository', () => {
   afterAll(closeInMongodConnection);
 
   describe('findOneAndPopulate', () => {
-    it('should find one message by id, and populate its sender and recipient', async () => {
+    function toArray(value?: string | string[]): string[] {
+      return value ? (Array.isArray(value) ? value : [value]) : [];
+    }
+
+    it('should find one message by id, and populate its sender and recipient (with mid being a string)', async () => {
       jest.spyOn(messageModel, 'findById');
       const message = (await messageRepository.findOne({ mid: 'mid-1' }))!;
       const sender = await subscriberRepository.findOne(message!['sender']);
@@ -67,8 +71,38 @@ describe('MessageRepository', () => {
       const result = await messageRepository.findOneAndPopulate(message.id);
 
       expect(messageModel.findById).toHaveBeenCalledWith(message.id, undefined);
+
+      const expectedFixture = messageFixtures.find(
+        ({ mid }) =>
+          JSON.stringify(toArray(mid)) === JSON.stringify(message.mid),
+      );
       expect(result).toEqualPayload({
-        ...messageFixtures.find(({ mid }) => mid === message.mid),
+        ...expectedFixture,
+        mid: toArray(expectedFixture?.mid),
+        sender,
+        recipient,
+        sentBy: user.id,
+      });
+    });
+    it('should find one message by id, and populate its sender and recipient (with mid being a string array)', async () => {
+      jest.spyOn(messageModel, 'findById');
+      const message = (await messageRepository.findOne({ mid: 'mid-2' }))!;
+      const sender = await subscriberRepository.findOne(message!['sender']);
+      const recipient = await subscriberRepository.findOne(
+        message!['recipient'],
+      );
+      const user = (await userRepository.findOne(message!['sentBy']))!;
+      const result = await messageRepository.findOneAndPopulate(message.id);
+
+      expect(messageModel.findById).toHaveBeenCalledWith(message.id, undefined);
+
+      const expectedFixture = messageFixtures.find(
+        ({ mid }) =>
+          JSON.stringify(toArray(mid)) === JSON.stringify(message.mid),
+      );
+      expect(result).toEqualPayload({
+        ...expectedFixture,
+        mid: toArray(expectedFixture?.mid),
         sender,
         recipient,
         sentBy: user.id,
diff --git a/api/src/chat/schemas/message.schema.ts b/api/src/chat/schemas/message.schema.ts
index 302db508..4200e367 100644
--- a/api/src/chat/schemas/message.schema.ts
+++ b/api/src/chat/schemas/message.schema.ts
@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Hexastack. All rights reserved.
+ * Copyright © 2025 Hexastack. All rights reserved.
  *
  * Licensed under the GNU Affero General Public License v3.0 (AGPLv3) with the following additional terms:
  * 1. The name "Hexabot" is a trademark of Hexastack. You may not use this name in derivative works without express written permission.
@@ -20,11 +20,11 @@ import { StdIncomingMessage, StdOutgoingMessage } from './types/message';
 @Schema({ timestamps: true })
 export class MessageStub extends BaseSchema {
   @Prop({
-    type: String,
+    type: [String],
     required: false,
     //TODO : add default value for mid
   })
-  mid?: string;
+  mid?: string | string[];
 
   @Prop({
     type: MongooseSchema.Types.ObjectId,
@@ -96,9 +96,12 @@ export class MessageFull extends MessageStub {
   sentBy?: string; // sendBy is never populate
 }
 
+const MessageSchema = SchemaFactory.createForClass(MessageStub);
+MessageSchema.index({ mid: 1 });
+
 export const MessageModel: ModelDefinition = LifecycleHookManager.attach({
   name: Message.name,
-  schema: SchemaFactory.createForClass(MessageStub),
+  schema: MessageSchema,
 });
 
 export default MessageModel.schema;
diff --git a/api/src/chat/services/message.service.spec.ts b/api/src/chat/services/message.service.spec.ts
index 8952c244..b47a6872 100644
--- a/api/src/chat/services/message.service.spec.ts
+++ b/api/src/chat/services/message.service.spec.ts
@@ -107,6 +107,9 @@ describe('MessageService', () => {
   afterEach(jest.clearAllMocks);
   afterAll(closeInMongodConnection);
 
+  function toArray(value?: string | string[]): string[] {
+    return value ? (Array.isArray(value) ? value : [value]) : [];
+  }
   describe('findOneAndPopulate', () => {
     it('should find message by id, and populate its corresponding sender and recipient', async () => {
       jest.spyOn(messageRepository, 'findOneAndPopulate');
@@ -116,8 +119,13 @@ describe('MessageService', () => {
         message.id,
         undefined,
       );
+      const expectedFixture = messageFixtures.find(
+        ({ mid }) =>
+          JSON.stringify(toArray(mid)) === JSON.stringify(message.mid),
+      );
       expect(result).toEqualPayload({
-        ...messageFixtures.find(({ mid }) => mid === message.mid),
+        ...expectedFixture,
+        mid: toArray(expectedFixture?.mid),
         sender,
         recipient,
         sentBy: user.id,
diff --git a/api/src/extensions/channels/web/base-web-channel.ts b/api/src/extensions/channels/web/base-web-channel.ts
index 97ab1944..52383de2 100644
--- a/api/src/extensions/channels/web/base-web-channel.ts
+++ b/api/src/extensions/channels/web/base-web-channel.ts
@@ -241,7 +241,7 @@ export default abstract class BaseWebChannelHandler<
           ...message,
           author: anyMessage.sender,
           read: true, // Temporary fix as read is false in the bd
-          mid: anyMessage.mid,
+          mid: anyMessage.mid?.[0],
           createdAt: anyMessage.createdAt,
         });
       } else {
@@ -250,7 +250,7 @@ export default abstract class BaseWebChannelHandler<
           ...message,
           author: 'chatbot',
           read: true, // Temporary fix as read is false in the bd
-          mid: anyMessage.mid || this.generateId(),
+          mid: anyMessage.mid?.[0] || this.generateId(),
           handover: !!anyMessage.handover,
           createdAt: anyMessage.createdAt,
         });
diff --git a/api/src/utils/test/fixtures/message.ts b/api/src/utils/test/fixtures/message.ts
index 5f70796a..d2496bbd 100644
--- a/api/src/utils/test/fixtures/message.ts
+++ b/api/src/utils/test/fixtures/message.ts
@@ -9,7 +9,7 @@
 import mongoose from 'mongoose';
 
 import { MessageCreateDto } from '@/chat/dto/message.dto';
-import { MessageModel, Message } from '@/chat/schemas/message.schema';
+import { Message, MessageModel } from '@/chat/schemas/message.schema';
 
 import { getFixturesWithDefaultValues } from '../defaultValues';
 import { TFixturesDefaultValues } from '../types';
@@ -27,7 +27,7 @@ const messages: MessageCreateDto[] = [
     delivery: true,
   },
   {
-    mid: 'mid-2',
+    mid: ['mid-2', 'mid-2.1'],
     sender: '1',
     recipient: '1',
     sentBy: '0',