Builders warehouse port elizabeth

I went to them to get a geyser for my place and I had no pronlem with the gentleman in who which one to go for and gave me a product code to go pay for it and that's when it all went down hill... The cashier apparently didn't know that she must not use a certain card machine for certain accounts any who she swiped and it went on my side but because it was a rcs card it had to be another machine then the supervisor lady tells me she has to refund it and I can't get the geyser because their books won't balance... And then the so called manager Auntie comes and tell me sorry there's nothing they can do... Which was their fault in the first place now I had to cancel my plumber because of their incompetence in appointing proper cashiers and management to be able to sort out a minor incident I can only imagine it was something else..... Utterly disgusting and disappointed in they're costumer relations and lack of decency to people purchasing there.... They better hope the refund reflects soon or they will ***..