Double charge

I took a cash trip yesterday and as we got to our destination we paid the driver R74 as that is what was the amount requested. I didn't think anything of it or to go back into my Uber app. Today when I wanted to take another trip a pop up appeared in my Uber app saying that we had not paid the previous trip and I now need to settle this R74. No where in this app does it allow me to speak to Uber support as the options prompted on the app is minimal. I tried writing a story but Uber is not helpful. This is the 2nd time this is happening to me the first time I got the driver to call me bacck saying I lost something in order for him to fix the error on his side. This is ridiculous Firstly I have to now pay back that amount if I want to use uber again and secondly the support from Uber is not user friendly I'm not able to email or message support and actually tell my story as they have selected options to choose from when making a complaint and that's pathetic actually. I use Uber regularly and I need them to fix this error as it's a huge inconvenience for me cos today I had to get someone else to Uber me since I'm not prepared to pay for a ride twice