Forum Discussion
When the meeting starts, we’ll let people know
For starters, this is not a bug. Rather it's the Teams app that doesn't handle multi-accounts / multi-tenants particular well at this point. In general you should be signed in to Teams desktop and Outlook desktop with the same account to avoid issues. When clicking a meeting link and being signed in to Teams, you need to be signed in with the associated account/org. to which the invite was sent (or enter as anonymous guest not signed in). If not Teams is going to use the signed in account/org. credentials trying to access a meeting in which they weren't invited to, hence being stuck in the lobby as not being recognized (that is if not "everyone" is allowed).
So this is a combination of using the Lobby options as an organizer and which tenant you're currently signed in to.
Using InPrivate / Incognito browser sessions is an alternative if having issues with the app.
Choose who can bypass the lobby
Change participant settings for a Teams meeting (microsoft.com)
For a deep dive Meeting Lobby Behavior in Microsoft Teams : Jeff Schertz's Blog
When a Microsoft Teams meeting is organized by person in Company A with somebody in Company B, the organizer sometimes receives the following message. "When the meeting starts, we'll let people know you're waiting".
Neither the organizer or the participant can enter the meeting. However, this does not occur on every occasion indicating that this is bug rather than an admin setting.
A workaround is for the person in Company B to set up the meeting inviting the person from Company A. However, this is not ideal since you don't know which meetings this bug will effect.
When will Microsoft fix this issue?
PS this issue never occurs with Zoom (or other competitor products), reflecting the superior market share enjoyed by Zoom!