A lot mail from nextcloud community

An user gets a lot of emails from the Nextcloud community. How can this be reduced? She isn’t even a member of Nextcloud community. She only is an user in my private Nextcloudarea.
Can anyone help me asap?

What mails, from this forum, a mailing list or from your NC setup?

From this forum. In the subject, the followin text: [Nextcloud community]…

Then she registered to this forum. In the profile settings there is a point where you can set when e-mails are sent to you (daily summaries, answers to your questions, …)

Well, she did not, that’s the strange thing about it.
I already figured it out. Thanks anyway.