Changed SIP port number


having problems dialling out after changing my sip port number from 5060 to 50509

everything working am able to receive calls in and ext to ext works

but when i try to dial out let say my cell phone it doesn’t do anything just fails and says the number is not answering

but i am seeing and error:

WARNING[57499]: chan_sip.c:4019 retrans_pkt: Retransmission timeout reached on transmission [email protected](my public ip address):50509 for seqno 102 (Critical Request)

my phone is aastra 480i it did pull the correct config with the correct port numbers…my ext does have the correct port number and the sip config also has the correct port number…also tried to disable the firewall and still the problem exists…so am kinda confused

any help would be really appreciated