Discovery unable to offer me a R1,700 refund from a closed credit card account

I closed my Discovery card earlier this year, and after the closure I received a refund of R1,700 to the credit card from a Computicket transaction refund. Despite numerous attempts and requests to Discovery over the last 2 months they have been unable to arrange the refund to my current account, blaming FNB for their inability to do so. I am extremely frustrated at this poor service and for continually having to chase them up and wait for them to resolve.