iPhone XS \\ Problem with protective glass with different manifactures

Good morning,

I have a problem with protective glasses.

Since I bought the iphone XS (11 months ago), I replaced 3 protective glasses because bubbles always come out in the same place (See image below). All 3 have different manufacturers. After the third, the Apple support (Very Cordial) replaced the touch screen of the phone, but I got the problem again with the fourth protective glass, (fourth manufacturers). I don't understand what it depends on. Are protective glasses available from amazon that thousands of users buy and I haven't found anyone with the same problem in other communities. I'm also willing to buy a glass protective from the Apple store, but if it happens again? This is a imperceptible curvature of the phone / screen / other?

Thanks for your attention!