Still Being Debited

I had called the contact Centre yesterday to cancel our household building insurance policy held under my parents name. After my father had confirmed his details as the authorized contact and confirmed his intent to cancel, I had asked if our account would be debited and was assured that it won’t be. We had tried the day before but that department was closed and prior to that, our call was cut. Nevertheless, today the debit order has reflected as going through. Why are we still being debited? Policy OT***