diff --git a/src/WAConnection/4.Events.ts b/src/WAConnection/4.Events.ts
index 41e154a..b4bd036 100644
--- a/src/WAConnection/4.Events.ts
+++ b/src/WAConnection/4.Events.ts
@@ -404,7 +404,7 @@ export class WAConnection extends Base {
             }            
             // only update if it's an actual message
             if (message.message) {
-                this.chatUpdateTime (chat, toNumber(message.messageTimestamp))
+                this.chatUpdateTime (chat, +toNumber(message.messageTimestamp))
                 chatUpdate.t = chat.t
             }
             chatUpdate.messages = newMessagesDB([ message ])