I migrated a user from an IMAP email account by exporting all information to a .pst file using Outlook 2016. I verified that all folders and email in fact were exported. I then imported the data into a newly created Microsoft 365 email account using Outlook 2016. All folders and files imported perfectly and the Microsoft 365 account began synchronizing the data perfectly. I logged onto the Microsoft 365 web interface and found all of the folders to be there.
I then began to setup access to my Microsoft 365 account. It authenticated, and began synchronizing. However, all user created folders (User created folders, except inbox, sent, deleted, etc) are not visible on an iPad / iPhone. I've confirmed this on multiple devices. If I create a new folder in Outlook 2016, it is visible, but the preexisting folders are not. Any thoughts would be greatly appreciated.
Is there some type of formatting issue when exporting IMAP folders that prevents the iOS device to not see it?