Paint Adhesion Issues

[Bigdawgracer]

Hi All,

Hoping someone out there can help as this issue is starting to bug me big time!

I’ve been painting shells for 30+ years with great results.

However, the last couple of years, after a few weeks, the new paint on my shells has begun to peel off!!
Normally pulls away under the Velcro at the sides but also in other areas untouched by anything…
Paint comes off clean in these areas, polycarbonate is left looking like new.
Always wash the new shells in warm water with washing up liquid or hand soap. Tried both and swapped when issue started!
Tried new tins of paint but result is the same.
Thin coats, left to go off for 10-15 minutes between coats.

Really at a loss now….

Feels like the inside of the shell should be keyed up with scotch pad or something but that sounds so wrong!

Also, any advice for repairing or stripping these areas? Can’t afford to replace shells just because the paint falls off!

Any advice please guys, much appreciated.

Thanks!