I have made experience with sim 800l, it works like a charm. Now I got a new SIM900A module, interferencing it with (RP over python), AT command returns ok, and other basic AT commands, so not the communication with the Chip is the question.
I starts up, sim card is inserted, seems it is working, until I'm missing that the sim card is registered to the network (it is a tested sim card, I used it over and over successfully in sim800l, no PIN required, so this is also not a problem).
So I enter: AT+CPIN? then I get: PH-NET PIN which means on the man: network depersonalization required.
What is depersonalization and why is it required, and better: how to solve this?
