Overcharged when APP says something less

My Bolt driver demanded I pay him 90 when my original ride was 29. We made a turn and the ride costed 39 and he demanding I pay him 39 rand three times and I told him I did not have it. I was scared because it is late and that driver was just rude and did not even help me open his trunk so I could put my suitcase. The way I am anxious because not only am I now low on cash but I'm also shaking of terror. I complained to Bolt but I have nit received a response yet. This was completely ******** and that driver was intimidating and the worst part is that he knows where I stay even now I'm scared of complaining. I am really appalled shame this was a ******** thing to do honestly it was *******