Dear brothers i have a problem and need help

I WILL Explain to you so maybe u can help

certain voip lines like telekom germany works only from their internet , isp must be their internet
i am trying to register with this lines from my rdp using proxy and proxifier but i alwayes get _error_ registering this lines , the _error_ on zoiper (sip phone , ip phone ) do not read the proxy and i get _error_ that dns is worng
maybe because proxifier uses tcp ports and lines uses udp ports

when i try to log in with this lines from hacked rdp Telekom germany it register and call normally

when i try to use proxy+proxifier and use profile for all system , all borwsers read that i am telekom germany other app also but only ip phones do not wrok and appears errors
there is any thing to do with proxifier to improve his work and let ip phone work from proxy ?

if any one have solution please contact me on telegram

i am willing to pay also
thank you