Fiberglass coating over concrete pool lifting at edges

[Liz1603]

I have an old Sylvan concrete pool, installed in 1961. In the mid-90s we paid several thousand dollars to have it coated with fiberglass with a lifetime guarantee against cracking or peeling. The company is now out of business, and the coating is starting to lift around the edge of the lip. Any ideas on what to use to seal the edges to prevent water from going under causing further lifting? Thanks.