I cannot delete my account and poor service

Poor Service - I cancelled my account towards the month of January and their system kept on saying I cannot due to internal problems. I could only cancel it the following month, on the 3 Feb and I got billed. I called support to complain and they said - they don't recall their system giving an error when customer wanted to cancel their subscriptions. Now my banking details are still on their system and it says the next billing is in April. I'm just defeated. I also haven't received any email or SMS saying my account has been cancelled!