Ridiculous service I want my refund

On the 07th April 2021 I called the call centre for assistance to order a greenbacks card since I could not be assistant at one of the nedbank branches in Kimberley,due to my greenbacks program not being linked under my name, to my suprice I was told I had been de-linked from the program in March or May 2019 so they said, I couldn't understand coz they kept deducting the loyalty fee every month and only stop in April 2021 after my call. The reference number I was given for this was ***6 and a query was then logged for greenbacks to refund the payments. 19 April I called again and nothing was done greenbacks insisted I was de-linked REF ***April I called again for feedback, greenback had responded with an approve mandate on the case whom they approved on the 20th alrdy but still no refund 5 May 2021 I called again with no change they still were waiting for the greenbacks department to approve bear in mind that, I was told it should take roughly 3/5 working days 13 May still no refund with a new REF ***5 still nothing 20th May I called again since I sow they refunded me with R48 wich was ridiculous. I was de-linked on the program in March/May 2019 but they kept deducting money until April 2021 no Ref was given my call had been cut off.... Nedbank I may not be correct but in 2019 the loyalty fee on greenbacks was R22 and 2020 it was R23 and in 2021 it is R24 so how the heck do I get a refund of a R48 my number is ***. I