Shifting blame and not taking responsibility

I went to Shoprite in Schweizer Reneke to buy electricity for my mother to my disappointment it didn't load I called the call centre but to no avail I then went to the Municipality to see if there is a problem at their side but only to find that all is fine from their side. I then went back to Shoprite but and they called the call centre who said I must go home and call from home but on my way home I went to Werda to biy another coupon and I punched it in and it worked it loaded 30 units and after that I called the call Centre who could not help even after all the instructions he gave me and he ended up giving me a number to Polokwane and there they gave me a field managers number who advised me to go back and claim my money but to my disappointment the Branch manager told me there is nothing he can do as they does not refund even after asking him to assist he couldn't do anything I ended up leaving without my R70 I bought for with a voucher that was not working . I really don't know how can people sell something but not have a alternative plan for situation like this as they are supposed to have an agreement with the supplier should they encounter such problems.