How To Enable Admins/Users to Import Their Own PST files in Office 365

To enable the admins/users to import their own PST files, the users must be given the “Mailbox Import Export” role.

This it how you configure / assign the users the role.

Login to the Microsoft 365 Admin Center and Open “Exchange” admin center.

Click “Permissions” > “Admin Roles” and “+” Add a new role

Enter details (example info), Add “Mailbox Import Export” role. Click Save