I think there must be at least one more variable as to why a user cannot be seen. I can show you a case where two users have both their profiles set to 'organization' visibility (Who can see your profile?). One can be found, the other cannot.
You might want to check if the role of the user permits them to join groups.
サインインしたメンバーは投稿、更新のフォローなどができます。初めてですか?無料アカウントを登録してください。
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