Hi @Michel welcome to the Atlassian community.
May I know what invitation link you are trying to register? the invitation link if you wish to login with a different credentials, then try opening the URL in the incognito browser. This way, the Atlassian tool won't automatically sign you in but opens the intended page.
Stay safe and stay healthy.
For JSM June Challenge #2, share how your non-technical teams like HR, legal, marketing, finance, and beyond started using Jira Service Management! Tell us: Did they ask to start using it or...
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