MONEY OVERPAID TO A BOND THAT THEY DO NOT PAY BACK!!

my sister had a bond that was administrated by LGR Incorporated. She resides in NZ and had to settle this. There were numerous mails between herself and Refilwe Theledi. In the end, I had to settle this account . This all started in Sept 2017. Unfortunately, I paid a excess amount of R10000 to much. My sister, by mails i have, has asked that this amount must be paid over to my mother in her ABSA account. Now THIS is the problem. I have power of attorney for my mom, still in SA. I have been dealing with a mr Shaun Hugo at ABSA for ages and every time it's a different story. I have sent proof of her account ect ect ect. My sister has also requested this by mail, but up to now, Feb 2018, NO MONEY!!. it seems if you owe money, it has to get settled asap, but when they owe you, you can for ages. As i have stated, my mom is a pensioner and could do with this money. At this stage, I am so fed-up, but really do not know who to turn to!! Is there any one out there that could assist? For this seems like a lost case, but R10000 is a lot of money just to let go!! Leone v Rensburg.