Hi @Nadia-9627
By default, registration is only open until the end of the meeting unless the organizer enables and sets a different registration end time. You won't be able to reopen registration after the meeting. This is by design.
For Teams webinars, meeting links never expire. As long as you send attendees a participation link instead of a registration link, attendees don't need to register to join. In addition, it allows anonymous participation in meetings.
The difference between the participation link and the registration link is as follows:
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