Cancelled contract - Another debit order went off...

I cancelled my contract on the 2nd of January 2020. This was the month's notice. Thereafter, had to phone 3 more times to confirm that the service was cancelled and they will no longer take debit orders. Guess what.... 3 February 2020 another debit order has gone off. They have no way of cancelling other than telephonic calls. Really no respect for a person's constitutional rights. This is disgusting....