Can’t login to Facebook app

Hi everyone,

I have a problem with Facebook, Messenger and Instagram applications on my phone (iPhone 8 plus) because I get an error message when I want to login which says: “Unexpected problem. Please try again to login.”. But I can login from my laptop and from Safari browser without any problem. I reinstalled the apps, restarted my phone, did factory reset, network settings reset, settings reset and updated the iOS software for the newest one but the problem is still there. And I tried to contact with Facebook but I got no response. I do not know what should I do so please give me advices, ideas to solve the problem.
Thank you,
Ákos