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This is really strange and I hope someone had this problem before so you can help me out.

I've used 3 different phone to call the DID call back (5713137218). Out of 3, only one phone works. The other two phones will get a busy tone when calling the DID. My phone, in particular, reaches the DID, it hangs up automatically within 2 seconds then it will call me back and I can perform the call just fine.

Is a call even reaching your Asterisk server when you dial from the two phones that don't work? Asterisk's 'sip debug' or wireshark/tcpdump are your friends.

I realize the problem is that if the caller ID wasn't registered then it will give that problem. I forgot that I already got my phone CID registered. Is there a way around this?