mildays credit stinks -- between them, absa and fnb they are happy to never credit you

my sister bought clothes end april 2021and used her card from the netherlands to pay. she returned the clothing beginning may 2021 and miladys refused to refund her or issuing a gift voucher. instead they reversed the transaction via the card machine using the card from the netherlands. it is now 23 november. we have been battling endlessly to get them to issue a refund or a gift voucher. the money never showed up in the bank card from the netherlands. they are directing us to absa, and now latest to fnb. they refuse to help us and expect us to try and fight with banks while my sister is sitting on another continent.