Your site is asking you to login twice
WHAT: You're trying to log in to your website, and you are asked to input your username and password. The first time you do this, it's rejected. You try logging in again with the same exact username and password, and you are able to log in.
WHY: This happens because sites that have a custom login path (ex. /dashboard), need to have that path excluded from caching to prevent the double-login issue.
HOW: Contact email@example.com and let us know. We'll make sure your custom login path (ex. https://mysite.com/dashboard) excluded from your cache so you don't run into this issue again with your site.