Indeed, it is often difficult to deal with all sent and incoming applications when you use several mailboxes at the same time. But to avoid confusion I use one very cool app https://www.outlooktransfer.com/the-best-microsoft-outlook-tips-and-tricks-for-email-management/ This application allows me to quickly navigate through all incoming emails and organize my activities in the most optimal way. I advise everyone who works with correspondence to use this program.