Debit Order

I had a credit card with Discovery Bank which I cancelled 8 years ago .I am still being debited with R100 every month. For past 8 eight years i have not received any renewal credit card from Discovery.I have phoned Discovery Bank on numerous occassion explaining to them this card was cancelled. Discovery Bank must check the history on this account for the past 8 year they will find that there was no transaction apart from the R100 debit being charged to me. I request Discovery Bank to refund Me with interest all the monies that they deducted from account for the past 8 years.