Hello, thank you for reaching out.
- May I know whether you’re able to send and receive emails when you access your account online through a web browser?
- Are you using a personal Microsoft account or a work/school account?
- Are you using Classic Outlook or New Outlook?
Since you can send and receive emails normally after restarting the Outlook app, it appears the issue may be specific to the app.
Have you tried signing out of Outlook and signing back in with your account? Also, have you tried resetting or repairing the Outlook app?