Telit Python Issue

Wireless & IoT
1

My module stops working any time I try to use the MDM.receive command.

import SER
import MDM

SER.set_speed('115200','8N1')
SER.send('hello world\r\n')

a = MDM.send('AT+CREG?\r',0)
res = MDM.receive(15)
SER.send(res)

SER.send('\r\nDone! \r\n')

If I remove the receive and ser.send commands, it works fine.

Any advice?