I want my R450 refund

I didn’t received my refund still and no one to assist from the 1st of Sept rain took R450 from my bank account without my knowledge- I have been asking for refund since then- they said they refunded me I don’t have money in my bank account- I even asked if I should send the statement- I have many references for this issues- come month end they going to debit me full amount while the owe me - I asked them to use it for credit but my statement doesnt show credit - they claim on the 04 sept refund was done - I don’t have that R450 - I don’t know if it’s a **** they did or what I don’t know - also their sms said our accounts are up to date we should not worry didn’t say anything about refund