Admittedly having Zip experience with the named vendor, I can say that back when I was rep-ing for a national sail maker I learned a bit of sail making trivia. Also have a friend that was selling sails (two decades) for a decent sail maker out of Hong Kong. He put a lot of time into customer advice and support, and the sails were quality dacron, and were indeed a little less expensive than the big sailmakers.
But, doing business with an unknown company via the internet nowadays is pretty much like answering a one-column-inch ad in a 1950 issue of Popular Mechanics, to acquire a perpetual motion machine. Actually, those ads were likely more honest, since the US Postal Inspectors would go after the advertiser for failing to provide the product. Buying stuff via the 'net is often a
lot sketchier.
Far better to just deal with a local sailmaker. Or a national brand with a local shop.
The OP may have just paid some tuition into the 'school of hard knocks', as have we all done.... from time to time...