Concerns with Recent Service

I'm writing to express my disappointment with the service i received from Tyrenet Point in Southgate Durban on the 19 December 2024. despite taking my car in for a major service, I was not provided with a detailed invoice or any documentation explaining the work done. Furthermore, I wasn't shown the old parts that were replaced and there was no discussion about the entire service process. They were only interested on one issue a misfire problem picked up and there was no diagnostic report about that issue. upon driving my vehicle back home I was disappointed to find that the performance issues persisted. Specifically, the car struggled to drive up the hills. I am left with no choice but to request a full refund of R3100 as I'm intending to take my vehicle to a reliable service provider. The manager was not cooperative, she was screaming at me. Upon receiving the invoice and the work done, I noticed a significant discrepancy between the services provided and the expected scope of a major service. the work done doesn't meet my expectations and I'm extremely dissatisfied.