New boy on the block

[McCreed]

I sprayed the same bass with duplicolor mica green, came out great, clear coated with polyurethane,

Ooooh, yeah. That was destined to go wrong.
Acrylic lacquer like Duplicolor (or any lacquer) will continue to gas off under polyurethane, and the solvent gas will soften the poly from the bottom up.

The general rules are: Lacquer over poly, OK - Poly over lacquer, NOT OK.

[McCreed]

I have also been told to let the paint completely gas off before applying topcoat. That may be more of an acrylic thing, but fully curing should at least give the the top coat less to react too.

I have applied clear immediately after the base coat has flashed without issue, with both automotive acrylic thinned and sprayed through my gun, as well as Duplicolor rattle cans. I'm 99.9% sure (it was 2 years ago ) I allowed the Dulux base coat to gas off at least over night.
I have no logical reason for the reaction that followed other than "stuff" happens .