What if your car handbrake does not go down what do you do?

Answer 1

If your handbrake won't go down, leaving your parking brake on, you wouldn't want to drive it until you can fully release the parking brake.

if you drive with the parking bake on, it will heat up the rotors of your brakes, possibly warping them, and you will lose all braking power until the rotors cool down.

that could easily cause a collision.