Looking for a good app (as cheap as possible) to recover deleted facebook messages

As the subject shows, I am looking for an app that will allow me to retrieve deleted facebook messenger messages. I am sure it possible..everything is possible with a computer and nothing ever really gets deleted...right?

Any suggestions would be greatly appreciated.

Yes, except when it comes to server side stuff that you don't necessarily control. Services like these keep their data on cloud servers and send them to clients to keep, once you delete the information locally, it might (or might not) delete them from the server as well. Any local data recovery you might use has no effect on what is stored on the cloud and you can't do anything with those..

Would be interested to hear how you managed to delete them as mine go back years and I haven't a clue how to remove them.