Disappointed customer

I bought Haval H2 Luxury 2020 model in 2020 February. In 2024 May it started giving me problems mixing water and oil. I booked it in at Haval Amanzimtoti,Durban. They kept my vehicle for more than 2 months only to receive it on 23 July 2024. I was advised that I should replace car battery which I did on the same day 23 July 2024. A week later the battery was malfunctioning, car not starting and I went back to battery center and complained. Battery was tested and found to be in a good condition. I went back to Haval and they ran a test and told me nothing wrong with the vehicle. In October I bought a new battery different brand Willard. My car ran just fine for about a few weeks. I booked my car back for service on a Monday 2 December 2024 and reported the fault to them. I was again told checks were done and fault repaired. On Tuesday 3 December 2024 vehicle did not start giving reading that battery was low. I booked it back again and was told they don't know what the problem is. I decided to change dealership and sent it to Haval Durban. I picked my car on Wednesday 11 December 2024 and was told problem was fixed. On Thursday 12 December he problem started again, battery low , vehicle not starting and had to jump start it. I called the dealership again and was informed to return vehicle for checks. I am failing to understand how can they fail to identify what the source of battery drainage could be. I'm also failing to understand how can a vehicle manufacture tell me they don't know what the problem is. I have never missed any service, my mileage is only 60 000 km. I'm very disappointed in the brand and will not again go for it in the near future