Q2501 Hanging

the Q2501 module is hanging when it is taken from one service provider to the other.
the symptom’s like the module works fine all of a sudden it stops responding and after a long gap, it starts responding but, no GPS data is available. the state continues until a restart of the device is done. it’s very urgent to solve this problem. can someone help me out?
also, are there any at commands that will allow us to manually select service providers?
Thanks in advance!

6.2 Operator selection +COPS

Thanks for the reply. but, i would like to know why the gsm hangs. what are the possible reasons for it hang?
most of the time it requires a restart of the device. also, incase it reconnects, why is the gps not fixing? it requires a restart to return to normal.


           I need WismoQ2501 model CPU urgently.If sombody know the stockers . Kindly  sent to me some stockers list.I need the price details for Wismo Q2406A&2501.