Haval Ontdekkers road roodepoort...Poor Service

Took my vehicle for an engine light,I was advised to pay for diagnostics which I did, after the diagnostic i was advised to change battery, I did that and still had the same issue of an engine light and took the vehicle back to the dealer, they told me that the battery size was wrong I then went back to the battery center changed the battery to the size wanted by car dealer and still the engine light came up.

Now dealer (service department) says I must pay another fee for diagnostics and I refuse to pay because they did the diagnosis and did not do it right instead advised me to buy a new battery meanwhile original battery was tested and proven fine.

Vattery centre did test the original battery and told me that the battery was fine, yet dealer said I have to change the same battery and I did.

My last question to them was why did they say after the diagnosis I must change the battery and I did that and still the problem persisted and when I tell them they say I must pay again for a diagnostics.

I even decided to trade the vehicle back because of my experience with them... Poor service I have received honestly.