theft of voucher

I went with my wife to upgrade her cellphone contract at he springs mall branch. We were in the area for the weekend. The first person we found did not even attempt to assist us and instead went to sit down, another kind gentleman came to our aid, he helped us with the deal and everything ran very smoothly. We upgraded to the Samsung Galaxy S9, we bought a body glove screen protector valued at R300., which he kindly put on for us as part of the service. A week later, my wife drops the phone, the cover falls right off of the phone and breaks in half. Since we do not live in Springs we went to our closest branch at woodlands in Pretoria. The service there was exceptional. He told us we could not get a refund or replacement as it was not bought at his store but he offered to make us a new one at a small fortune of a fee. He then asked us to use the R800 voucher we received with the phone to cover the cost. We asked him, 'what voucher'. Iv been reading the reviews and it looks like a lot of the branches are opening the devises and handing them over with the customer non the wiser to the voucher being neatly placed one side and not ever given to the customer. Had i known it came with one, i would have insisted. Is this really the way vodacom wants to lead South Africa into the future? I am disgusted.