FNB refuses to reverse a credit card purchase done a year ago???

A friend and I did a payment to STA travel pre COVID 19 from our FNB credit card in Jan 2020. Following the high rise of COVID 19 infections, my friend got FNB to reverse her payment of R30, 000 but FNB refuses to action on my behalf , a reversal of R3000. My private banker, nor anyone at FNB can conclude this matter. I am tired of following up, emailing and calling. FNB is unfair and NOT consistent in how they deal with their customers!!!