Problem with user authenticacion to in Standard Plan


When my coworkers (whitelisted by me) click on the invitation link to my app, they're prompted to the login page. So far so good. There, they click on Login with Google (as my company email is with Gmail) and select their account. But instead of being directed to the app, they're prompted to a "Create a account" page, which is confusing since in principle they don't need this account to login.

If they go back to step zero and click again on the invitation link, then they're directly prompted to the app and everything's good now. But this is not a valid solution since this process is not intuitive and straightforward.

How can I make them go directly to the app when they enter their Google user/password?