

So the bottle doesn’t break, it just pops open? This still sounds like a packaging issue. Maybe unstopper / squeeze / stopper the bottle, so it’s got negative pressure. Maybe replace the cap with some other more permanent type of cap (one that doesn’t have a little flip-top, if the ones they’re including do, just a solid cap and then ship the flip-top one alongside it)? IDK. How is it coming apart in transit? It’s not literally the plastic bottle breaking, is it?
Why not just replace it with a cap that isn’t a flip-top? Screw it on tight, squeeze the bottle slightly before putting the cap on so there’s a slight negative pressure. That would be my first thing to try.