BBT are a bunch of liars and theiving low lives, whom trap you with the so called ficticious contract. If they have not provided you with the service you have paid for then instead of letting them get away with it, let them send you a bill for ending your contract early. They want money and will lie through their back teeth to keep you and your hard earned money. Log every call and take names and write times down times and dates.
Find another provider, cancel your direct debit as soon as poss. send a detailed letter, ask for any re- inbursements for poor service and unsatisfactory equipment and state that you want to end the contract.
The thing is what ever services they provide and are crap do you want to continue paying BT every month?
Let them send you the bill, you make sure you have another provider lined up and ready. The bill should come after you have ended the so called contract.
Don't communicate with them. keep copies of your detailed complaints etc. Don't pay for anything that was not satisfactory and complained about.
When you receive the nasty letters regarding the bill, offer them £1.00 per month by letter in good faith.
BT have tried to exploit their customers for too long and they'l continue to tell you lies as what proof have you got when you have spoken to all their staff in India and Britain . End your contract so you don't have to deal with them anymore and they won't get your custom.
They will send several engineers, check your lines, send you more equipment and tell you whatever you want to hear.