Buying a car from me

I contacted webuycars groblersdal to buy my car so after a few days they showed up on the 18th of January 2024 the lady looked at the car everyrhing was good and we went for a test drive 12kilos we came back she asked me how much would I want other rhan the price they gave me... she said she will put it through she didi not rell me there was a waring that the car gave out she only told me about the warning rhe day after and that was when I asked her when will they let the lady sign the car off rhe she told me about the warning how does that work waa she not suppose to tell me that on the 18th of January