Apparently a successful backup and restaration but... Problems

Restored from Sony Xperia X (F5121) to Sony Xperia X (Dual F5122), but never had the same, mostly smooth experience again!

I don’t know where to start… Here are some of the symptoms: The phone answers calls, but Android apps crash most of the time. Connections to the Jolla store and the Google store cannot be established anymore (worked for a while, i.e. the installation of the apps worked). WLAN connects, but after a while no more traffic! The installation of keyboards with other languages does not work anymore.

Any ideas how I can solve these annoying problems?

Please help

Sadly i have to share the same experience transfering from Xperia X (F5121) to Xperia 10.
A lot of Android Apps wich worked well dosent even start or hang.
Also there is no smooth experience anymore. Most of the time the Appdrawer is very jerky.
I’m thinking of reinstalling and manualy copying my phone book. But that’s very 2005.

Also after importing the Gallery via Backup ( wich has taken about forever ) all my Photos are 90 degrees counterclockwise …