Payment Not Reflecting on Builders Website

I bought something online this morning. My credit card was charged by the bank but the Builders website says they are awaiting payment. After two attempts, I managed to get through to the call centre, only to hear a party going on in the background. The call centre agent had to phone me back because of all the noise. She then told me I had to get a PDF proof of payment from the bank so the Finance department can, at some point, transfer the money to my account. How long would that take? What kind of online shopping experience is that? Also, the agent said she did not know if the bank would provide such a PDF. So, why request it then?