Worst accounts department ever

I joined car track 3yrs ago and within a year after joining them my car was a write off and I was told I had to pay a lump sum to cancel my contract because I signed a 3yr contract which I understood and BCOS I didn't have the money then I continued with the monthly premium. July finally came and my contract was supposed to have ended so I assumed the premiums would stop unless I call in to renew my contract but no, they debited my account twice till I reversed 1 amount then I was flooded with emails, WhatsApp msges & SMS about my overdue account. My question is don't your records show when a contract has ended? Why wasn't I told that even after my contract had ended I still needed to call to get my account cancelled? Now I'm being constantly harassed and I don't need this as I have never skipped a flippin instalment in the 3yrs with you.