Unfaithful driver claimed the money i already paid cash

I feel like for what happened today even a 1 is too good for a rating. I ordered stretwise two during lunch todady, i chose cash payment option. When the driver came i gave him R50 rands my order was R49,90. But later i saw that he reported that i never paid. I am very annoyed when i think of it, my wallet is on a minus. Am i expected to pay R100 for 2 pieces of chicken? Noways. And few weeks back i received a missing order when i complained i was told to liaise with the restaurant directly, i even gave up because the process was just too long. This has become utter *******. I would rather cut off my ties with them than pay double for my order. I even saw that guy putting the money in the pocket. His name is Amani, uber eats its complete ****