Acedining Full-Coverage Tempered 3D Glass ($10)
Unfortunately, reviews on Amazon are fake and extremely misleading. If you look up "Galaxy S9 screen protectors" the first three results are great products, which are already in our roundup.
The next few products on Amazon have 5-star reviews from over 2,000 happy customers. If you actually read those reviews, they're all fake. It's a freaking mess that's getting out of hand.
As a result, we physically tried and tested every screen protector in this roundup. So while we recommend Spigen, amFilm, IQShield, or Whitestone first, you can also try this screen protector from Acedining.
They promise you're getting quality over quantity. Instead of a 5-pack of garbage screen protectors, they'll give you two good ones that actually works. You'll get a 9H tempered glass protector with matching colors and curves, which covers 100% of the phone front. This one has fake reviews too, but it fit my Galaxy S9 perfectly. If everything you've tried failed, and you don't want a film from IQShield, give this one a try.