I changed the battery in my key fob now the vehicle won't start

Hello, replacing that battery should have little correlation with the engine being able to start. However just for fun, have somebody check to ensure the battery has been correctly installed and is the proper application for the fob. Hands on testing is needed. https://repairpal.com/auto-repair-near-me

For quite sometime now. I took a friend's car to the dealership to have them put a battery in my key fob after returning home and attempting to start my vehicle it would crank but not turn over. I had it towed to the dealership and after a week they contacted me and said I had to make a decision to pay them $ 2,995 because the computer needed to be replaced It was starting every time before they replaced my key fob battery. I need help , I don't have that kind of money. Can anyone tell me what I should do ? I feel like I am being Scammed.