Hello
It sounds like you might be receiving fake/phishing scam emails.
If you go to https://account.microsoft.com , sign in, then click on Microsoft storage to expand that section, how does the storage look there? Good?
Are these emails from microsoft.com address? Feel free to copy and paste an example email so I can see if they are trying to take you to non-Microsoft website. Please remove any of your own email address reference when you share, to protect your privacy.