Not happy client

I was selling my car they came and gave me a offer which I excepted I bought the car a month ago and I wanted to sell it in the same month because of a job opportunity that araised and I didn't need a car I changed ownership on the car the car was in my name they requested a sales agreement from the previous owner which I supp**** then they requested it to be commission which I supp**** then they requested the previous owners ID which I supp**** they wanted all these information which a sale agreement was sufficient then they wanted a video affidavit from the previous owner stating they sold the car to me they ask for all these information it's like I was selling them a ****** car which his on my name even if it's in my name for a month the license department had no issue the roadworthy had no issuse but we Buy cars sellers have a issue i.even made they previous owner to call the seller to tell them they sold the car unfortunately the previous owner didn't want to make a video affidavit because it a silly thing to do On we buy cars website which I saw doesn't state that if a vehicle is less than 6 months old in your name these are the requirements to have or do This will be my last I ever use we Buy cars to sell or buy a vehicle and I previous bought and sold vehicles at we Buy cars