"He who marches out of step hears another drum." ~ Ken Kesey
did all of the ink flake off or just a layer ? that quick it may be inter-coat adhesion (over flashing).
My guess is that you're exceeding the elongation of the ink--because it's only flashed. The ink film is pretty weak when it's only 'gelled'.Same thing happened to me with that ink on some UA shirts, the only solution I could find was less tack.