Welcome back to our Community and for posting to our forum wall; I was sorry to understand that you're having some issues with your landline. Account telephone numbers can't just change, there is a complex process if a number needs to be changed for any reason - if you have not requesting this, it may be a line fault.
I have located your account from your forum information and without going into any account detail, I can confirm that you still have the same landline number linked to your account since you joined our family.
Please dial 174 or 175 from your landline or dial a mobile and see if the number matches the one on your online account. If they are indeed different, then this is a line fault called a Crossed Line and a technician would be required.
Pop back with updates when you can (no need to post the number here - we'll Private Message if we need to)
Thanks so much for popping back, sorry I missed your reply before I left for the evening.
I have gone ahead and booked you a technician visit; you can check the date and time of this visit via your online account at anytime. If the slot is not convenient, you can also reschedule via your online account.
I'll also pop you a Private Message so you can pop me a reply with the number you are currently connected to and I can provide this to the technician. Look out for the Purple Envelope in the top right of the page and pop me a reply when you can.
Thanks for your Private Message there @irrwoodAlfie
I can confirm that your number is still your number on your account so it does look to be a crossed line. There is no reason the technician can't get this sorted out for you during their visit. I have also updated your account with the number you're crossed with.
Please do feel free to pop back with any updates so we know how things went.