Fxo caller id help

using tdm400 2 fxo ports and 2 fxs ports.
a pstn line connected to fxo port 2. and both analog phone connected with extension 333 (port 3) and 444 (port 4)
when i call into d pstn line using different pstn line or mobile phone why am i receiving caller id from 444?
if i unregister both analog phone and why i get “unknown” why i dont see my mobile number as the caller id?? :question: