Verify

1. That the PIN code has been removed from the SIM card.

2. That there is a contact on the SIM card called PINCODE and where there is a four-digit number in the field for the phone number. Often it is necessary to manually copy to SIM card, otherwise it will only be stored in the phone’s memory.

3. When trying to make a voice call with the SIM card when it is inserted in a mobile phone, it is important that someone answers at the other end so that the welcome message disappears.

If the error still persists, it may be the GSM module that is not working. When the telecom operator “closes” a SIM card, a code is sent that may cause the Ontech GSM module to crash. This has to be replaced. Contact support@ontechgsm.com in that case.