Unread folder doesnt appear in outlook app tree

Hello,

I'm attempting to utilize the Outlook app on my iPhone 15 Pro Max to retrieve all my unread emails from the Unread folder I've established on the Office 365 server. I've set up numerous subfolders in Outlook with rules to direct incoming emails to their corresponding subfolders. Due to the growing number of subfolders and the volume of emails I receive, I've created a new subfolder on Office 365 where all unread emails initially reside. Once read, they are automatically directed to the appropriate subfolder based on the defined rule.

While using the Outlook app on my iPhone, I expect to see the same folder tree structure, including the Unread folder. However, for some reason, the Unread folder does not appear in the tree.

Any suggestions?