wrong facebook app

Hi.

I had my wife's old Iphone 5s as a secondary phone next to my main android.

When i started to use it, i resetted with my own apple id, and deleted my wifes.

Finally spared money to buy an iphone 11 pro max.

Upon activation, I copied the data from the iphone 5s, making it easier to start the new phone.

Still, nothing visible from my wife's account , neither apps or anything related to facebook.

Still, when I download ANY application, which can be paired with Facebook ( normally that is the way i sign into apps ) will be automaticly will be connected to HER facebook.

There is no other option to change the log in ID , just HERS.

at the beginning it was just frustrating, but now it is way worse.

Started with little games, now even food ordering applications.

The worst in this situation, is for few months we even live in different countries.....

any solution to this matter?

Or shall I restart the phone from scratch again?