t28p problem link status disconnected, registered extension with asterisk

[joseluisp]

We have a t28P remote office with firmware 2.60.0.140 with a public dynamic IP in a NAT environment. We have port forward SIP port (5060-5080) and STUN (3478) in the router to T28p internal ip. The phone is registered with a central office (asterisk freepbx). The problem is that link status show "disconnected" in the tab "status" of phone and when you phone to remote extension, remote extension back to say "reject" with 404 or 486 message.

Thanks in advance.