Being ignore from HO and online chat after purchas

Went through the clearance sale this morning online and came across a washing line selling at a value of R0.00 Selected item and continued to check out, did payment (delivery charge) then while processing the banking screen went over to the home page. Opened online chat support and stated that i ordered an item, paid for it but got no invoice. Chat came back asking for name and Credit card detail to check. Waited for 40 min after last chat from Grabit read \give me a few minutes". Phoned head office to say i have been waiting forever to give me feedback"