Vacation hub international worst company ever

We were members for 10 years and end of Dec 2024 we were to get our loyalty cashback for R17 500. Needless to say we did not get that and then they wanted a reliance certicate which we never received. I told them in Dec my last payment will be end of Dec. 2024 and in Jan the said I musy still psy for one month before they can cancell my denit order. The now debit me each month with different amounts and different dates. How can I get rid of this dishonest bunch of people. Please help