Hello Antonio! My name is Janbaz, and I am an Independent Advisor.
I'm sorry to hear you're having this problem, and I hope I can assist you to find a satisfactory solution.
Please check your OneDrive storage on the link below to see how much OneDrive space you have.
Outlook Storage
https://outlook.live.com/mail/0/options/general...
You can delete the message and attachments from your OneDrive that took a lot of your mail storage, and you don't need them.
I have attached a screenshot where you can look to.
Changes to Microsoft 365 email features and storage
https://support.microsoft.com/en-us/office/chan...
Please let me know if this doesn't work or if you need further assistance.
Disclaimer: This is a public user-to-user community forum. None of us here work for Microsoft and it is beyond our capability to assist directly with the account or login-related issues.
Warm Regards,
Janbaz
