Got my dump trailer back in March. I have probably used it about a dozen times or so. Noticed the other day that there's a big spot and several other small spots on the floor of the bad towards the rear that are totally peeled away to the bare metal. Obviously dumping and scooping things out with the shovel is harsh but is this normal? If it is normal do you just let it go? Or should I try sanding and using some spray paint in those areas or my just fighting a losing battle?