My OATH2 submission keeps getting rejected

They provide the reason: App cannot be reviewed (entry link does not exist, sign up flow is broken, etc).
I’m not sure why they won’t accept it despite me being able to use the website myself. The login process is working correctly yet I still get rejected.

You probably already have it, but is the website public? and add a button somewhere on the landing page that says “Login with Roblox” that’ll link to the sign in page.

I did that then got approved after. I removed it though since it’s gonna be integrated with my discord bot