******** debit or *****

They debited my money without my consent and amount of R1278, while I already paid R550.40 that's was due for this month, when I asked them they said they will do the reversal , when I check they only return R700 where is the other money because I don't owe them I already paid for month of March, the next payment will be due in April. I sent them an email they didn't respond.