Sim808 bluetooth problems

I am working with the sim808 by bluetooth, but I have a problem when I send data the information is divided into segments. when I receive it also arrives in fragment. I need your collaboration as a specialist in the area.

This i am seeing for first time. I always get full string at a time on my SIM800C. I have tested with SIM808 also earlier. It gives continuously. I never got this +BTSPPDATA URC. May be you have enabled something to get this.

I do not understand that it can be only I have connected by the SPP protocol and from the beginning this problem happens to me. I can not recite the information in a single package.