Error

Error #0360: you can't edit messages older than XXX minutes
 

Error description

You are trying to change your own messages but allowed time already passed.

 
Problem solution

In MyChat, you can't edit messages for any period of time. This limitation was added to avoid confusion in conversations.Thus, the maximum time period for editing messages is set on the server. By default it is 15 minutes. An administrator can increase or decrease this time.