Question about Facebook messaging on my phone?

[K B]

Ok a few days ago I was talking to the 2 people on fb and then randomly messaging quit working so I couldn't send anymore messages to them. The next day I went on and in my messages both there names say "Facebook user" I can't find either of them in my friend and when I click to go to their profile from messages it just says "page cannot be found" so I cannot talk to either of them and I know they didn't block me. So what's the problem and how can I fix this?

[Oshama been laden]

A b c

[Alex]

you are chatting using the phone?
U might have been run out of credit or your phone has network error.
Try refreshing your network and clear all cookies and history.
hope this help.

[thesourcex]

It's possible that you can't find them because they deactivated their accounts hence the page can't be found