Pass DID information to 3cx


I have UCM 6202. I had configured a SIP trunk line on Grandstream UCM 6202. The calls are routed through VOIP trunk to 3cx. I am able to route the calls to 3cx. But I am not able to pass DID information to 3cx to route the calls on 3cx with different DIDs.
How do I pass the DID information? If I disable Original CID it works perfectly but then I am not able to get the Caller ID on 3cx.

Thanks in advance