Unprofessional charging me ridiculous amount

These guys are ripping me off and I would like to query it hired a car took it from East London on Friday 6th June car is fine with no dents as I have a good profile with Avis. Fine whole weekend in Eastern Cape especially Mthatha there were heavy rain all over even so much flights had been postponed due to weather. I returned tge car in Mthatha Airport instead of East London as I was prioritizing safety as roads were too wet. Now these guys are charging me a a ridiculous amount of R600 to do a vallet yet the mats are not even that dirty they could have at least taken out the mats and dust them outside and use vacuum cleaner they don't even have mud but grass as ther was rain nonmid at all. Now im charged for that also the petrol was not even low low they didn't even attach a slip for transparency if like a breakdown and full reimbur*****t of valet explain why you charging me R600 this is a ******* from Avis Mthatha