trf 24g issue

Recently I got TRF-2.4g module, which one is master and other is slave. When master sends command (4 bytes) to slave, the slave sends 20 bytes, its nothing but query and response, these data send to serial port (115200 baud rate). It works fine, but it will stop after 800 times (aprox). Why it is stopping?. When I reset the master again it will receive 800 times stop?

1.In my Master program sending command configuring 4 bytes packet and when receiving configured as 20 bytes packet.

2.After the configuration of TX it requires 3to 4 ms delay, then transmit the data, without the delay it does not work.

regards

naga