Additional features, settings, or issues not covered by specific Microsoft Teams categories
Hi Daily,
Sorry for any inconvenience it may cause. Some users encountered the same issue and they shared a solution. Since you mentioned that you made sure you have no out of office events in your calendar, please go to OWA(Outlook Web App), click the gear button> choose "Mail"> Mail> Automatic processing> Automatic replies> tick "Don't send automatic replies" to turn off out of office setting.
If the issue persists, please check if there is any invitation mentioned "out of office", then remove it and check if it works. This may take some time. Thanks for your understanding.
Regards,
Carlos