Useless Ubereats

I've ordered from Uber ears twice. I don't really like their app because I don't find it user friendly but in order to get a more accurate delivery I used them for work purposes. Last month I noticed that they had been charging me R50 and I disputed it.

They responded via FB messenger and explained that it was the subscription fee of R50, so that throughout the months I could get free delivery. However, in checking both the app and online it showed that I did not have a monthly subscription. I explained this to them and they repeatedly explained to me that I have to cancel it. How must I cancel something that doesn't exist?

Its really disappointing to come across yet another company who lacks the initiative to help a customer, rather than reading off a script handed to them. I cannot find a contact number for them, so I can't even speak to a human being. My only contact is some person on the other side of a computer with an attitude.