Mudi V2 GL-E750 still no Internet (German Telekom APN)

Hey,
I just bought a Mudi V2 GL-E750 and can't get Internet access. There are some old threads here where these APN settings are recommended:
internet.telekom
User/Password: telekom/telekom
I have tried every possible combination of APN settings. Also internet.v6.telekom and internet.t-d1.de, but no success.
The SIM card connects to the LTE net, but no internet.
Firmware is 4.3.19r3

Any idea what I can try?

Thanks
Pat

Hello,

  1. Is this SIM card Internet normal when it inserted i the phone?
  2. Please provide the following screenshot of GL GUI -> Cellular, and execute the AT command at ··· of the top right corner of Cellular: AT+CREG?

@PaddyLu
Try to access pass.telekom.de
Does it work?
You‘re trying to access near a border?
Try Roaming=Off