Servive Complaint

We went for a full service at Supamac on the 25 March 2022, amount paid was R 2930.00 via EFT. Our car make and model is Nissan Juke 2016 Silver Grey we bought the car at WP Motors in the year 2018 November, we were referred by the dealer to SUPAMAC for future car servicing. Our car was in a excellent condition, we serviced the car every year when its due. This year when we in March the 25th we went for latest service, when we got there the boss was on vacation. We enquired the price which went up to R 2930.00 and we proceeded with the service, my husband took in the car. He left the car there for major service around 9am and they called around 12 to collect the car, he arrived there around 1pm to take car. He did not notice anything wrong as the car has been always been in a good condition. After 3 weeks we then noticed the indicator light flickering which shows that the car has not been serviced, I myself spoke to SUPAMAC whattsapp according to them they did not have any records of the latest service they picked up the 2019 as the last service. For us that was already an indication to say service was not done, on top of that my husbands name and surname was incorrectly spelt on the invoice which has never happened, he noticed that and he called them and the lady said they will correct it and send an email which was received after a week being reminded twice. The first time we went in we told them that the car was not serviced and showed them the sign and they denied, they used diagnostic machine. The second time when we went there they mentioned water in the engine, they said they cleaned up the water which we were not convinced. We left few minutes after the same sign came back, we returned for the third time as we noticed that the car was losing power and it was making an sound from the exhaust pipe which we never experienced these signs on the car. We were fustrated thinking about our safety and the money we paid all together. When we got there we informed them the state of the car and sound, the car jaggling it was not normal as we know our car. They asked us to sit down, my husband was with them while they were reviewing the car. When they opened the engine theyve noticed that 3 plugs were burnt, and they said at the moment they will replaced and asked my husband while they do it. They finished without giving us the full report on replacing of the plugs instead they told us to come back following week for them to replace something which will amount to R900 x4 which is not part of the service. The car needed just to be serviced, that is what we needed and paid for meaning that we paid for something that was not done