It sounds very much as a broken bottom module!
You may find more information e.g. here:
If your phone is under warranty you may open a ticket.
If not you may buy a new one.
EDIT: You may also try to clean the contracts first. It might help.
EDIT2: As you wrote your warranty is over and you’re in hurry you might consider buying the module in a shop in Germany. It might be delivered faster.