Mdot: Error while receiving packet from LoRa Gateway

Hi,
I modified the manual_example code in Dot Examples to make mDot transmit and receive packets from LoRaWAN gateway. The transmission and reception is done using Things network. Packets are being transferred to the gateway from mDot but an error occurs while reception. AT firmware for the same is working properly. The module works in Class A mode.
The error received is that the packet is not received and operation is timed out.
I am using send() function followed by recv() in the code.
Cold you help me with what I am doing wrong?
Thanks