Wrongful debit

On the 11th Jan I register as a new Ubereats client. I inserted my card details as a payment option. placed my order ,when it was delivered I was told I need to pay cash ..which I didn't have at the time hence the card payment option . I later discovered that although I made a cash payment an amount of R50 was taken from card . I sent an email to their support to query this and one of the replies did acknowledge the R50 but there was no mention of why it was debited or when it would be refunded . I am bit dissapointed with their service as a 1st time user .