Over charged

I went to do gelish nails on Friday around 11:30 at Sorbet drybar Greenstone. I paid R310. Then when I got home as I was bathing 3 nails came off. I then took pictures and sent to the lady who was doing my nails. She then asked me to come back. I went back and I then said to the lady I won't be coming back again if the nails will come off again and I asked if perhaps I should out acrylic instead then that means I will top up the difference from the R310 I have paid already? And she said YES. Indeed she did my nails again and I was very excited then when I was done and went to pay "the difference " to my surprise they took R500 from my credit card instead of R190. When I asked they told me it's because it's new nails. I then started to be aggressive as well cos the lady who was doing my nails assured me that I will top up from the R310 I had paid 2 hours ago . Then the owner Lynn came and she called security on me and THREATENED me that she will blacklist me and banned me from the mall. And I asked her if your employee said I could top up from what I have paid already why are you threatening me and say all that you saying bcos my complaint is not about paying as I've already paid R810 for your employee mistake why nit reprimand her as she mislead me had she told me I would have to pay R500 extra I wouldn't have agreed instead I was gonna ask her to refix the gelish I did an hour ago and came off.

Lynn is ****** and insolent and I will make sure I discredit her and will make sure no black customers will go to her salon. She's EVIL. Bad bad bad bad service.