OK - I will assume that the summary is correct then.
Now that "no longer in service" message that you hear when trying to call one of the lines has me concerned. That sounds like Verizon may have "turned off" the service, or otherwise disconnected it, OR perhaps is having trouble with their network. So you will most likely need to contact them directly (I have their main service number below) to look into this.
Verizon Customer Support: 1-***-***-****
BUT, if you would like to do one more TEST - I have the steps below.
1) Disconnect ALL devices from ALL phone connections (jacks, direct wiring, etc.) for ALL lines.
2) Leave the lines disconnected and WAIT 5-10 minutes.
3) While STILL having EVERYTHING disconnected, place a NEW TEST CALL to both lines - one at a time.
4) If you STILL hear the "no longer in service" message for both lines, that will confirm that this is a "service issue", and you will want to contact the service provider as soon as you can. Their support number should be available 24 hours a day - every day.
NOTE: If the "no service" messages goes away, it would be safe to reconnect ONE DEVICE ONLY - and TEST for a clean a clear dial tone.
Please let me know what happens when you try this TEST or if you have any other details or questions for me.
Thanks, ***** *****