Managing personal Outlook.com account settings, security, and privacy
Hi Antonio,
I received this too. Microsoft suddenly started charging me $11.30 CAD for Microsoft 365 Basic on the Hotmail account I have been using for free for 20 years. It has nothing to do with storage on your account. Microsoft scares people into thinking you will completely lose access to your account, but it's not true.
You can cancel the subscription at any time, and you will not lose access to you email account. I just did it. Microsoft just charged me today. I clicked My Microsoft Account in the top right corner --> Services & Subscriptions --> selected Cancel Subscription. If you do this as soon as you are charged, Microsoft will refund your money.
Hope this helps.
Daniela