Uber is robbing people

I have contacted Uber over two months ago regarding my apparently credit of R260. I paid the Uber driver in cash R350 and they are tell me that I need to paid that money in order to continue to use the app. This is not my first time this has happened with Uber, the fact this has happened more than once is unacceptable. They have not responded to my emails and no action has been made. This is actually rude and poor customer service.