Hi ayo 94,
Welcome to Microsoft Q&A forum.
If this is an Outlook.com/Hotmail account and the account truly was never inactive, then the inactivity policy may not be the reason. Microsoft says an Outlook.com mailbox can be closed if it is not signed in to at least once in a 1-year period, and the Microsoft account itself must stay active by signing in at least once every 2 years.
Please first check the mailbox in Outlook.com on the web, then look in Deleted Items, Recover items deleted from this folder, Junk Email, Archive, and any custom folders. Microsoft notes that messages removed from Deleted Items are only recoverable for 30 days, and messages in Junk Email are also automatically removed after 30 days.
If the old messages do not appear in Outlook.com on the web and are not in the recovery folders, then unfortunately there is no supported self-service way to recover mail that is no longer in the mailbox.
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