Fidelity ADT *****ing Money - Failing to stop debit orders

I have ended my subscription with ADT in July 2018 and up to date May 2019 they are still debiting my bank account.

They stated that I have a 24 contract with them, but they cannot provide me with a signed contract where I agreed to a 24 month contract. Only a form with my contact details, bank details and address was ever signed.

BE AWARE before you sign up - Once they debit your bank account you will not be able to stop the debit order and you will be paying indefinitely.

I have received information from a client of mine where ADT have been debiting their account incorrectly for over 7 years before it could be stopped and therefor they do not sign up for any debit orders anymore.

My bank stated that they cannot stop the debit order only the service provider can - Which is another complaint that needs to addressed all together.