Permission difference between running app from screen v.s. running from setting window

[Finalpredator]

On pixel 3a (probably not limited to this model), I met this strange problem. I have an app that would run if I long press its icon then go to "basic info" then select "open". But when I try to run it by just clicking its icon in my phone screen, I got a "app isn't installed" error.
Is Android system starting an app in different ways depending if I click its icon or run it from "basic info" window?

Extra info: the app is a game made through Unity. I tried multiple different builds (including signing with both default debugging key and production key, building full game, building just 1 scene, etc). All led to the same result that the game will only run if triggered from "basic info" window.

 

[B. Diddy]

Welcome to Android Central! Is this an app you're developing, or is it an app you sideloaded from the web somewhere (rather than from the Play Store)?

 

[Finalpredator]

It's an app I'm developing. (It can be downloaded from Play Store by searching "dessert shop manager").

 

[B. Diddy]

OK, I moved this to the Software Development forum for more specific traffic.