syedsalmanalam
Newbie level 4
I am having some problem with my SIM900D, at first its got connected to the network but now it does not connects to the network. I check the AT+CREG command and the result is +CREG:1,3 3 means registration denied. I have this same problem with my old module then I changed the SIM900D SMD it worked fine with my interfacing board. Something is wrong with SIM900D. I have tested the module in other working interfacing board but still it is not connecting to the network. Please help me out (