Disappointing, Frustrating service from iStore on AI training

I booked AI training that was advertised by the Apple Istore in Sandton, and have had the worst level of communication I have ever experienced regarding the training. I was not able to reach anyone who knows anything when I wanted to amend my booking. I have paid for the training, but I am still waiting to receive the tax invoice I have requested numerous times. There is no-one to speak to (even though there is a customer service phone number). And noone who knows anything about the training program. I even contacted the trainer directly who tried to help. I am disappointed and frustrated!