how do i get bt to give me proof they informed talk talk of changover as i am still being billed after 18 months
It's not that simple, the switching notification is done via the suppliers, you asked BT to provide you services but were they like for like and did you retain the same telephone number ?
More info would help to get the right answers for you.
i am 81 so didnt understand much of that,same broadband ,no phone is all i can say
thanks
If you have a copy of the first BT bill and confirmation emails you should be able to email those to talk talk for proof that you changed supplier.
You can get the bills and download them via the MY BT account via the BT website or the My BT app if you have a smartphone.