Refund debit order on a closed account

Hi, I settled my account with Finchoice on Wednesday, they asked that i email them proof of payment, which i did, yesterday i got an email that is settled, this morning they debit my account, when i call them, i called three times, but they keep on sending me left n right, and they are so so rude, there is this lady called tishwale or something, all i want is that they refund the debit order they made this morning.