Recovering deleted messages
We believe that your chats are very important, and we work hard to make sure that you never lose them. However, in the case that they are deleted or lost for any reason, we cannot help you recover the messages because we do not store your WhatsApp conversation history in our system.
The good news is that there are several options for recovering lost messages. There are processes to recover deleted chats on: Android | iPhone | BlackBerry | Nokia S60 | Windows Phone | BlackBerry 10.
At this time, there is no process to recover your deleted messages on Nokia S40.
To transfer your WhatsApp chats to another phone, read this article.
To learn about how to export or to make a backup of your WhatsApp chats, read this article.
WhatsApp Support Team