Possible hacked Messenger account

[fpapps]

I have a messenger but it starts to give me errors. What I did was delete messenger and install it again. But it asked me if I am the rightful owner. I asked for a code which was sent to my number. After putting in the code, I could no longer access messenger. What did I do wrong? Is somebody using my account?

 

[Scienceguy Labs]

Log into Facebook from a PC and change your password to something new. On your phone, go into settings, apps, and click on Messenger. Clear cache and data. Then, force stop for good measure. After that, uninstall it. Power off/on your phone and redownload the app. Log back in with your new password.