This sounds like a case of a mixing issue. I've seen this a few times, and actually have has the same issue years ago.There was probably a small area in bottom of your bucket of unmixed resin. Be sure to scrape the bottom and the sides of the mixing container to make sure all the epoxy molecules mix. The resin is heavier and stickier than the hardener and will stay on the bottom unless pushed around with the mixing stick.Epoxy is an additive reaction (chemistry 101) and requires the resin and hardener to be measured accurately and mixed thoroughly so every 2 molecules of resin links with 1 molecule of hardener. The best thing to do is scrape off what you can and re-hotcoat the area. No problem.