Possible Causes: The stain was still damp/wet when you applied the finish, or there's excessive burnishing, or the previous coat of finish wasn't dry, or you aren't screening between applications, or you changed 'products' between coats, or the stain wasn't adequately wiped, thus, a heavy pigment was deposited on the surface
If the finish is peeling from a previous coat of finish or from the wood itself, then maybe there was a bad tack. Possibly, the surface is contaminated with things such as wax, oil, or soap.
What To DO: If you're experiencing de-lamination from the wood surface, just sand and apply the finish. If the problem is only with the surface, then screen it and apply another coat of finish.
(Some of the aforemention may or may not apply but they're there just as an FYI.) My best to ya and hope this helps.