[?]: Connection TIA <-> PLC S7-1200 via GSM

[pkovarik]

I want to connect the TIA software online with the PLC Simatic S7-1200 via mobile communications operator.
I've been advised to use TS adapter IE Basic (6ES7 972-0EB00-0XA0) in conjunction with TS module GSM (6GK7 972-0MG00-0XA0).
I've tried to put this module into operation, but I've never succeeded.
Whether I've tried TIA to connect from the modem through a fixed telephone line, or through GSM modem attached and tried to call the TS module GSM module (on the PLC side), TS module never responded, the call was not accepted and no connection was established.
Either LED indication has not changed, still shone only the green LED indicating connection to the network of mobile operator.
When I've looked online to the status of the module, everything was fine, that SIM inserted, the PIN was correct, the signal strength was good.
I've contacted the provider, ie. T-mobile CZ, but it was confirmed that the CSD transfers are allowed in the SIM.
TIA side is OK, when I've tried to establish a connection to another phone number (my cell phone), actually ringtones occurred.
Does anybody have a simple example of how to establish a connection to TS module GSM, step by step?
Is there necessary some special settings?