I'm able to send and receive calls using a Yealink T38G but the caller ID that shows on my cell phone when I call it says Unknown. I contacted my SIP provider (my local telco, not an official 3CX provider) and they show a different calling URI than I am seeing in my event logs. Let's assume the external number they provided is 1234567890 and the authentication ID is testID. I've replaced my SIP provider's IP with 220.127.116.11. What they are seeing come through is testID@18.104.22.168:5060 instead of firstname.lastname@example.org:5060. I'm also confused as to the device not identified message. I've fooled with the calling URI settings and various other things I found on the forums but none of those resolved the issue.