I have a motel with a KX-DT816 that when an incoming call comes in, it rings Room 115 (ext 115) and then rings to the front desk, but on the front desk phone, it does not appear to be an incoming call from the outside, it looks like a call coming from that room?

I am not familiar with the KX-DT816, I have downloaded the programming manual, but was hoping someone could point me in the right direction.

Thanks in advance.