我已经安装了Kamailio 5.2.2和FreeSWITCH 1.8，并且都运行良好，我具有以下设置：
kamailio
user authentication
user registration
user location
call routing
instant messaging and presence
FreeSWITCH
voicemail
conference
SBC - this can be used for topology hiding, transcoding, prepaid or playing audio messages within calls
other media services (announcement, IVR, a.s.o)
用户身份验证和注册看起来不错，而且当扩展名互相呼应时，它也出现在FreeSWITCH上，但是我收到SIP/2.0 480 Temporarily Unavailable，我不知道我的设置缺少什么了吗？