I'm having a frustrating issue with a Mitel 6930IL IP phone setup. One of our users is claiming that when someone tries to call their cell phone from these phones, they never receive the call. I've checked in with our network team, and they've confirmed that everything is fine on their end, so they believe the issue lies with the user's cell phone provider, Verizon. However, the user contacted Verizon, and they assured him there are no problems. He mentioned that when someone calls, his phone doesn't ring at all, while the person calling from the Mitel phone hears it ring once before it stops. I'm not sure what the next steps should be to resolve this.
5 Answers
Have you tried testing the call yourself? Sometimes, you'll need to experience it firsthand to really get to the bottom of what's happening.
You could also use VoIP protocol tools to check the call details. The call logs may provide a SIP response code that indicates what's going wrong. If it’s a carrier issue, you might see codes in the 400 range, like 480. It’s worth testing other mobile numbers too, since sometimes companies end up on block lists. Also, just double-check that the user isn't blocking unknown numbers — I've encountered that issue a surprising number of times.
Interestingly, other mobile numbers work fine, but it seems to just be this person's number. I hadn’t thought about the call blocking; I’ll check that out!
Does calling out work? It might be worthwhile to swap the Mitel phone with another one nearby to rule out port or switch issues. A factory reset on the 6930 could also help it pull down the programming again.
You might want to escalate this issue to the network team so they can run some packet captures. That way, they can identify where the call is dropping off.
Okay, I'll take that back to them for further investigation.
One more thing: if you escalate it, make sure they test calls to a few different numbers. If it’s only happening with that specific cell number, it might help narrow down the issue.
Yeah, I got the same result when I tested it.