They do not want to refund me my R1000

I bought a part in 2022 which i later returned the same day and the store assistant told me there is no refund. So i told them i want a boot locker for vw which they ddnt have so they told me they do not have but they will call me when they have. Months went by and i always called and they said the part is not available and when i went later i fount to let in their premises. They never notified me as a client but then i went to Wannenburg Mayville and when i got there i showed them my credit receipt and they told me they dont have the part but they will contact me when they have. They wrote my details in their book and i told them that the receipt is going to expire as it was almost a year. Johan and the other manager told me that since they have my contact my credit wont expire even after a year it will still be valid. I have been going there for the past2 years but still they said they will call or they give me the runaround. I asked for refund because its been long and I think now they are taking advantage because I am a woman and I am black that is why they keep giving me stories. I sent an email later the auditor which did not state their name said my claim is not valid because i only came last year but its a lie because i have been going there for the past 2 years without getting help. My concern is that they are quick to answer my email but they did not even take time to investigate my claim. I want my refund of R1000. Its a lot of money for them to **** me. Johan and the other manager told me the assistant whp helped me at the shop was fired because he was doing all shaddu deals but on the email the auditor said he went on pension. I am very dissappointed with the service and the treatment they have been giving me.