PG GLASS MONTANA-BAD CUSTOMER CARE!

So appauled by the service i got at PG Glass Montana in Pretoria. I had an appointment at 12 to fit a new windscreen. I get there 15minutes before the time, the guy starts working on my car. Then the lady that works there says that other people were there before me. BUT, i had an appointment! My windscreen replacement was part of my insurance claim, but the lady working there insisted i pay an access of R1000!!!Which however was ridiculous after telling her i have a waiver. This branch is incapable and their customer service is pathetic.