Hi, I'm John! I will help you with this.
For a regular Teams meeting, you can invite up to 1,000 participants (including view-only). If you go beyond that, the extra participants can join in a view-only experience, which supports up to 10,000 people.
Reference "Request someone to join" section here https://support.microsoft.com/office/invite-people-to-a-meeting-in-microsoft-teams-4bc5981c-446e-4e93-866a-d757466b556a
If some of your invitees didn’t receive the invitation, it might not be because you invited too many, it could be due to a few other things, like:
- Their email addresses weren’t entered correctly.
- The invitation went to their spam/junk folder.
- There was a temporary sync or delivery delay.
Can I ask if you’re inviting people directly through the Teams app or from Outlook?
Click "Add comment" to let me know.
Regards,
John J.D.