UNHAPPY CUSTOMER

I am very disappointed in this shop. My mom bought by them a few years ago and that was paid up even though she wasn't happy with the stuff and the service, they phone SMS her to come buy again and promise her a 10% cash back after numerous calls and SMS she went to buy again that she will get 10% cash back which they promise her, then they promised her after she received her goods she can collect her cash at the store. my mom is a pensioner and was admitted in the hospital at the time so I went with her ID and the delivery slip then they told me there's no record that she qualify for the cash back I was furious because I was with her when she bought the goods and they promised the cash back they said they must phone the head office and will come back to me after a week I phoned but I didn't get through to the branch always engaged or the phone just ring. I went in to the branch and the manager let me sit and wait for 2hours then she say she must go to the warehouse I phoned again then she said they my mom is not getting the cash back as it is not on their records. my mom was very disappointed and say she will never buy there again