Employee requests client to shout for attention

I wanted to redeem a voucher at 17:35 today at the Pretoria North branch at 1 of the 3 kiosks, but had an issue. I waited quite a while, checking around for ANYONE to assist me. The was no employee in the front court, or at any of the tills and I had to go to the back to request assistance. Instead of apologizing, Ruben immediately insisted that I should not be there and should have called from the till counter to get their attention, to which I rep**** that I do not shout.