Ignored query on the app

I would like to express my disappointment in your service. I recently started using your services and I was initially satisfied by your driver's professionalism and my sister sang your praises about services until what happened today. I requested a cash ride on ubergo which was estimated at R43, when I arrived at my destination the driver said I should pay R78 and he even showed me the amount reflected on the app so I took the last amount I had and paid the extra amount with hope that when I raise it up with you it will be credited on my app but unfortunately that hasn't happened. I sent several messages for the past 11 hours pleading with you to look into my query but no feedback until now.