Hi Charlie H
Welcome to the forum. My name is Segunfunmi, and I am an Independent Advisor and Microsoft user just like you. I appreciate you reaching out to me with your query.
Alerts are notifications of changes to content on a site that you receive as email messages or text messages to your mobile phone, depending on how your site is configured. This article focuses on how to manage or delete alerts for yourself and for other users if you are a site admin.
To view and cancel your alerts and change the settings for your alerts, you can use either the User Information page or the Manage Alerts on this Site page. If you have permission to manage a site, you can also view and cancel alerts for other users by using the User Alerts page.
Below, I have included a link that may be helpful for further assistance.
https://support.microsoft.com/office/99dfb19c-9a90-4a8c-aba1-aa8c8afb0de2
I hope that the information provided has been helpful to you. If you have any further questions or concerns, please feel free to ask.
Warm regards Segunfunmi