Configure your CUBE router, and it’s connections to CM and PSTN.

Send your carrier call examples and escalate.

Date and time of call Calling number (main or outgoing DID) Pcap and sip messaging taken where the carrier connection terminates, and your pbx if applicable Number(digits)dialed

Repeat until you have at least a half dozen call examples over a day or 3.

Open a ticket with your carrier and escalate through your account manager.

As far as the Cell, you can “try” with att wireless, but as Ernestine always said “We dont have to care, we’re the phone company.” The cell is just verification the isdue is probably with another carrier or the called parties carrier.

Start by getting a phone that supports generic SIP and is not proprietary. The 7942 is EOL, and unless you load the 3pcc/mpp Multi-Party Platform firmware on it, it will only work with Cisco CallManager systems. In leu of a desk phone you could use a softphone on your computer, tablet or smart phone.