https://community.swisscom.ch/t5...

Some (more expensive) TomTom GPS devices have a SIM card and a GSM/2G mobile radio module built in. A radio-based internet connection is required for TomTom's LIVE service. TomTom GPS devices with an integrated 2G/GSM mobile radio module and an integrated SIM card realise the Internet connection via the 2G/GSM mobile radio network.

The SIM card integrated in the TomTom GPS device allowed roaming on the Swisscom GSM/2G mobile network in Switzerland until recently. The SIM card is almost certainly not a Swisscom SIM card. The mobile network currently used by the TomTom GPS device can be seen in the TomTom device somewhere under "Status" or "Info" or "Live services" or "Network".

The Swisscom 2G/GSM mobile network has the identifier 228-01:

MCC: 228 (Mobile Country Code => Country Code: 228 => CH)

MNC: 01 (Mobile Network Code => network number: 1 => Swisscom)

https://de.wikipedia.org/wiki...

It is unlikely that the packet data service of Swisscom's 2G/GSM mobile network suddenly stops working throughout Switzerland. There are probably TomTom-internal technical problems or the APN used by the TomTom-internal SIM card is causing problems in interaction with the Swisscom mobile network:

https://de.wikipedia.org/wiki...

In the case of APN problems, Swisscom could be partly to blame. Swisscom must forward the data sent to the "TomTom" APN to TomTom.

Side note: Swisscom will switch off the 2G/GSM mobile network at the end of 2020. From then on, it will most likely no longer be possible to use the live service of TomTom devices in Switzerland anyway! The mobile radio module currently integrated in all TomTom devices does not support 3G/UMTS or 4G/LTE mobile radio networks!

Source: community.swisscom.ch
Greetings
Roland