Wheel Well Undercoating Protection

2003 White LTD 4Runner

Has anyone had any problems with the undercoating protection not hardening in the wheel wells, still remaining a tar like substance? I noticed it first when it rained and it showed up on my white paint behind the rear wheel wells, I had to use bug and tar clothes to remove the substance? All four wells to some degree are still sticky or moist. It’s as if they were not cured correctly, or a chemical was left out of the mix.

One Toyota dealerships, close to my house in Houston, customer service/body shop knows nothing about this and in fact treated me like _____ because I'm a women. They had the nerve to ask if I drove through tar. To make my point I had to drag my hand on the top of each well, which left indents where my fingers were and the tar like substance on my hand.

My Sales person will take care of in Conroe; it’s just not close to home. Just wondering if anyone knows:

1. What the substance is?
2. How is it applied?
3. To what parts of the car is it applied?

Thanks for the education! Amy