Car battery problem since you installed your product

I am really now at my wits end that Carteack just can't sort my problem out for once at all. Juande you gave sent out a guy and he just didn't fo anything to my car he just suggest I take my car battery to a battery place to gave it charged. I believe the battery is not the problem I would rather believe it is your product that you installed into my car because I start having problem from day one. I suggest you either replace your product with a new one or you just come and remove your product out of my car because I cant carry on like this. I am dependent on my car to get from point A to point B. As a matter i need to go to the shops today but i am stuck because my car battery is as dead as a door nail. I am waiting in anticipation for a reply.