Unauthorized debits

CarTracker is a nonsense and bullies company, I joined them 2014 till 2024 (on which their contract it’s 3 years, after then you can cancel anytime) when i cancelled with them. The unit wasn’t working since 2018 but they kept on debiting money in my account. Fine I cancel with them this year Feb but even now they still debit in my account even after I have called them and cancelled. I reverse the debit order but they still debit like it’s a loan or I am still under contract with them.
Month to month I have to reverse while I cancelled with. Their consultants are very rude unwilling to stop the debit 😡😡 join them at your on risk. You have to call them every six months apparently to check whether the unit is still working or what while they debit every month.
I now don’t want anything to do with them but the problem they don’t stop debiting my account now they change dates 30/15/25/10 which is not the dates we have agreed upon! I feel harassed by them honestly and I call them with no assistance at all