Hi ​@PeeGeeR 

Thank you for your message.

Could you kindly confirm whether you're using an eSIM? If so, please note that eSIMs cannot be transferred from one phone to another. You would need to request a new eSIM for your new device. This issue doesn’t occur with physical SIM cards, but if you're experiencing problems with one, please try the steps below:

Manual Network Selection (Android):

Slide two fingers down from the top of the screen to open the quick settings panel

Tap the Settings icon

Go to Network & Internet

Tap SIMs

Select the SIM you’re using

Turn off Automatically select network

Wait for your phone to search for available networks

Select iD Mobile from the list

Michael Z