Hello,
When you sign in to Outlook on the web, do you see any rules moving emails to Archive or Junk? Go to Settings, Mail, Rules and remove any rule that redirects messages. Then check Settings, Mail, Junk email and review Blocked senders.
And then review rules and junk settings after securing an account since attackers often add rules to move mail. After removing anything suspicious, send yourself a test email and check if it goes to Inbox. Let me know what you find.