Landline disconnected by Talk Talk

Yngvar

iniltous said:

Have you tried calling  your old phone number , preferably from a landline ( a BT phone line ideally ) but by any method ?, if so , what happens , ringtone no reply , number unobtainable tone , busy tone etc..?, have any letters arrived at the address in something other than the family name , especially from TT ?.
Have you checked with TT that the account your mother had has been properly closed , has a final bill been received ?.
From the landline service in the house have you tried to make any calls to TT ‘ customer service’ , although they are not likely to provide any personal information about whoever is ‘renting’ the number they may offer some information, or have you checked  if it has an answer service on it , if anyone has left any messages for whoever this line should belong to 

Yes, the message says 'the number you have dialled is currently not receiving incoming calls'
Nothing has come to the house in anyone's name and TT confirmed that the account is now closed. 
We initially noticed the change of number when ringing someone and them telling us a different number came up. The next day, we couldn't dial out, instead we were put through to TT recorded message saying we needed to confirm some account details before making any calls (which we didn't do), and the day after, we were able to dial out again. Very confusing!
TT can't find any record of the new number, or any new account at the address
The only call we've had to the new number was a spam call - typical!

J_B

Many moons ago (late 2018), I asked Plusnet (who were labelled as John Lewis as well then) to stop my internet service but keep my landline.

They agreed, but then disconnected our telephone as well! (taking our number of 50 years as well)

Phoned BT and they had me a landline back working within 2 hours.

I then badgered BT to get my old number back. They could see on their systems that it was quarantined, but as soon as it was released, we got it back.

Maybe try to get a new connection and see if you can get the number back that way?