diff --git a/server/bll/event/scalar_key.py b/server/bll/event/scalar_key.py
index dd3c4e2..c74792c 100644
--- a/server/bll/event/scalar_key.py
+++ b/server/bll/event/scalar_key.py
@@ -111,7 +111,7 @@ class TimestampKey(ScalarKey):
             self.name: {
                 "date_histogram": {
                     "field": "timestamp",
-                    "interval": interval,
+                    "interval": f"{interval}ms",
                     "min_doc_count": 1,
                 }
             }
@@ -150,7 +150,7 @@ class ISOTimeKey(ScalarKey):
             self.name: {
                 "date_histogram": {
                     "field": "timestamp",
-                    "interval": interval,
+                    "interval": f"{interval}ms",
                     "min_doc_count": 1,
                     "format": "strict_date_time",
                 }