Rhino Linings did not honor lifetime warranty Nationwide

Around 2002, I had a Rhino Lining installed on my truck's bed to protect it.  I was assured I had a lifetime warranty on it by the vendor backed by Rhino Linings.  2017 rolls around, the bed liner is rolling back, bubbled up and separated from the bed surface at several points.  I had the issues documented by their current Rhino Liner dealer in my town.  Rhino Linings home office informed me they will pay half on getting the issues fixed.  How is half a lifetime warranty?  In the warranty's documentation there is nothing about pro-rating the warranty by the vehicle's age.  The damage was not from use or misuse, the material lost its adhesion over time.  I am the original vehicle owner and can prove it with my state registration certificate of the vehcile.  I am presuming Rhino Linings 'warranty' is based on their assumption the warranty ends when the vehicle transfers or is scrapped and that is about 10 years or so for the average customer.  I take care of my vehicle, its 32 years old and we are the original owners.   A warranty is only as good as the company that stands behind it.  Rhino Lining showed what its commitment is to its customers in this example.  If you plan to keep and care for your truck and want to get a good liner, look to someone other than Rhino Lining.  When a company so brazenly discounts their warranty to their customer others need to know about it.