Problem connect SIM900A in Brazil

Hi, I’m trying to use the SIM900A mini module, but I’m not able to make it sync with the operator, I’m feeding it with a 5V source and 2A I loaded the latest firmware posted on firmware-update-tutorials-appnotes /
1137B03SIM900A64 ST ENHANCE, it does not sync, I’m following the synchronization by the status LED it has on the module and it blinks fast as if I was looking for signal, I’m using a common POS PAGO chip with data and clear operator connection with support for 4 G, and I have a TTL adapter connected directly to the shield using TX, RX and GND, I already used some software to test the communication and it only responds to the AT command that returns OK and the rest with error.

NEED HELP :smiley:

SIM900A is made for Asian 2G networks. Its no surprise that it wont work in Brazil.
If you have 2G in Brazil, you need SIM900/SIM800 instead of SIM900A