Won R1600 instead of paying the suspended account saying it was linked to another account

My sister Delisile patricia mthethwa received R50 bonus that was then se played an won R800, she requested a withdrawal but it was declined without giving explanation.

She contacted them then they asked her to make a deposit then she did(R50) the she requested a withdrawal again it was declined again with any explanation. She contacted them again they said she must turn over that amount to R1500 of which she did it and requested withdrawal again it was just staying there pending. She contacted them again they said it will processed then she asked for complaints department contacts or should she go external route then they said they sent her an email.

The email said they closed her account because it was linked to another. How Is that?? After threatening them about complaining about them ?