Uber outstanding amount i know nothing about

I am not happy with uber app at all , its been long since i requested from this app because of the outstanding fee of R 85.55 I have, with them which i know nothing about. I tried to order food on the uber eats app today and still getting an error that i have to settle an amount of R 85.00. Like i said i know nothing about this outstanding amount, i messaged them to assist with investigating or removing that so that i can continue using the app , i received no call or reply from them.