Check the Activity log for the group.? It will say if she was removed for marking a message as spam.? Unfortunately, it may not have been done actively.? There are some email services that use a 'faulty' spam filter that puts things in the spam folder that it shouldn't.? Then, if the member doesn't notice and mark it as not spam, when the service automatically deletes it after awhile, it gets reported to Groups.io who removes the member.? This is required so that the site doesn't get a bad reputation causing the email service to block all emails from here.? It didn't happen on YG because they ignored the reports.
I don't believe there's anything in the Wiki here about it, but there are a lot of posts about it.
Duane
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