Fare increase for no reason

Unfortunately the app does not allow me to submit this query. Neither is there an email or contact number. Saturday 01 March I used uber twice. Both occasions I used the Wait & save option. The morning price was R172, I waited a total of 17mins but was in no rush. However, after the trip a total of R220 was debited from my bank account. The afternoon again I chose the wait & save option, price given was R153 this time I chose the cash option. Upon arrival at home the amount due was R182. I paid the full amount as I do not feel its fair to give the driver less. Both occasions we drove straight from pick to drop off no extra stops or different routes. The driver did not wait long either as we were outside waiting with both pick ups. I would like a refund on the balances owed. I think it would be wise to add an option to your Customer care option for "Other" with room to state what the other is.