Terrible Customer Service

Last week Tuesday I placed an order online, but I never got an email or sms confirmation for my order being ready for collection. I phoned their customer service and the consultant said that he can see my order, and he checked the stock availability at the store I was going to collect from and he confirmed that they do have more than enough stock. He said that I can go collect the item. When I arrived at the store, I gave them my order number, but store assistant said that he is not picking up the order on their system. I phoned customer service again, and she spoke to the store assistant, and then she said that she is going to lodge a complaint with the complaints department on my behalf. I got a call from a guy and he said that he was going to send me an email then I can reply with a proof of payment, and I never got that email. I phoned them again yesterday morning wanting to cancel this order. I later got another call from a lady who also wanted me send a proof of payment, and I also asked her to send me an email so that I can reply with proof of payment, but she also never sent an email.