Uber must fall

Over the last 2 month i been noticing uber gives you an amount when booking a trip. Later the night they reverse the amount and push through more that you never agreed to. I now removed my card dwrails from the app. Tonight i did a cash package uber. To collect my sons friends soccer gear for football. When he fot here he the driver charged R80.00. He had no change for a 100. Agreed to a credit and only R15 was credited. R56 to R85 is a big difference. What if i only had the R56.00. I sent them a complaint via the app. I got a 27.00back as i complained...but what about all of the other times.