Thanks for your feedback above which shared more information and glad to know that your issue is resolved now! Since our forum has the policy that The question author cannot accept their own answer. They can only accept answers by others, and according to the scenario introduced here: Answering your own questions on Microsoft Q&A
I would make a brief summary of this post so that other forum members could easily find useful information here:
[Activating lagged copies - Summary]
Issue Symptom:
I need to find a member, then delete them then add them again because Teams is buggy. This person was accepted but for some reason they cannot access the team still.
Solution:
add this new person 4 times, even thought they were already in. The 4th time finally worked.
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