Specific numbers can't be dialed from our PBX

[XcamaroX]

Fellows,

Recently I've had a few issues with certain numbers, when I call them the response is Server Internal Error and it never dials.

I have looked at the numbers and they are both from Wireless Carriers.

I have another PBX at a different location and the same problem happens, service unavailable. This other PBX is NOT a 3CX but Elastix.

At this point my only concern is my VoIP provider, which I have this brought up to their attention and they can't seem to know what the issue is.

This is the response that I get from my 3CX PBX:

08/22/2017 11:25:44 AM - Call to T:Line:10000>>xxxxxx987@[Dev:sip:[email protected]:5060] from L:2417.1[Extn:710] failed, cause: Cause: 503 Service Unavailable/INVITE from xxx.254.144.xxx:5060

08/22/2017 11:25:44 AM - [CM503003]: Call(C:2417): Call to <sip:[email protected]:5060> has failed; Cause: 503 Service Unavailable/INVITE from xxx.254.144.xxx:5060

I have tried both ways with and without the 1, to no avail.

This is from 2 different PBX systems, so it cant be something from my 3CX, so I would like if it's my setup or my provider.

What do you guys think?

 

[leejor]

If you send the number in the same format as all other similar numbers, then it's your provider.
They should be able to tell you what is happening. After all, it is them rejecting your call with the "Service Unavailable" message. Somewhere down the line, they are probably getting the same message from the provider/carrier that they pass the call onto.