Question about Reolink GO 4G

Hello, I have successfully activated the camera with a sim card from Digitec "iot data package". But when I insert the sim card into the camera, the acoustic message appears that the connection has failed. The SIM card is activated and the APN access point on the SD card is a text file that I downloaded from https://support.digitalrepublic.ch/de/support/solutions/articles/33000237038-apn-konfiguration-reolink-go. I adapted the content so that the APN access point is the same as on the SD card. I have adapted the content as it appears on the SIM instructions that came in the package: Name: dr. m2m.ch APN: dr.m2m.ch Username: Password: But it does not work. It also doesn't work if I enter it without "Name" as freshly downloaded. I have also reset the camera several times. If I insert the SIM card into a mobile phone and enter this APN, the Internet works. So it can't be the sim card and the APN. What could be the reason?