Misleading

Order said if you refer people to use app you get r75 off when purchasing over r100 and I had credit maybe too much for their liking and they took back or erased all my credit I have and I have proof that this was done they are misleading people into getting to use the app saying you will get credit but how can you take back something you already have the customer if rightfully it belongs to the customer as I never asked for the promotion...