diff --git a/.changeset/brave-ways-breathe.md b/.changeset/brave-ways-breathe.md
new file mode 100644
index 0000000000000..ebb4af0ba727f
--- /dev/null
+++ b/.changeset/brave-ways-breathe.md
@@ -0,0 +1,5 @@
+---
+"@rocket.chat/meteor": patch
+---
+
+Fixed outdated message mentions displayed in the UI after changing username
diff --git a/apps/meteor/server/models/raw/Messages.ts b/apps/meteor/server/models/raw/Messages.ts
index 49930a8c92ea9..1c5df883d8226 100644
--- a/apps/meteor/server/models/raw/Messages.ts
+++ b/apps/meteor/server/models/raw/Messages.ts
@@ -1214,6 +1214,7 @@ export class MessagesRaw extends BaseRaw<IMessage> implements IMessagesModel {
 				'mentions.$.username': newUsername,
 				'msg': newMessage,
 			},
+			$unset: { md: 1 },
 		};
 
 		return this.updateOne(query, update);