No customer service - waiting 3 months for repair

I bought a mobility scooter from Dis-Chem Carnival Mall and I had puncture that I asked them to fix in October already. Dis-Chem sold the item to me but never told me that they do not keep spares. I was told that they need to send it in for repairs. I have had endless problems with the wheels from day one. I have handed in the wheel for repairs in October. Since I have handed it in i never received any feedback. I am the one that has to phone and drive 30kl to the mall to find out what is happening. I then have to walk in the mall and it is a problem for me because i have serious back problems and that is why i bought the mobility scooter in the first place. I am a widowded pensioners and i do not have money for endless phone calls and petrol in order to try and get feedback. I have spoken to Chris the manger, Cliff another manager and Wilma at customer service. All i get it empty promises and lies. Today TOM from the service department sent me an sms and i had to phone him back. He told me that i must pay R350 into his bank account after i was told it would be R150. He then informed me that my wheel is lost and i must buy a new wheel! I want my wheel back fixed.