When clicking on Login .. embedded page previewer

When I click to preview my app, click on Login, I get a browser popup immediately, even prior to entering an email or password. The browser popup says:

An embedded page at previewer.adalo.com says
Invalid Email or Password
Please double-check  the information you provided and try again.

Is this an Adalo issue or have I potentially missed something?

Update: Although I have a logout in my app and use it. I also added an action to the login page that logs out the user when they visit the login page. Seems like this has corrected the issue.