If you have an image that was uploaded as a standard freeform image, you can convert that image so it can be used as a portrait image. 

To convert the image, you need to find the image in the "Photos" tab

Hover your mouse over the desired image and you will see several icons that you can click on. Click on the pencil icon to open an editing menu. 

Click the "Convert to a Portrait Photo" button

Then you can enter the name of an existing student or create a new student if you cannot find that person when searching. Click the "Save" or "Convert" button when you are done. Now this image will be moved to the "People" section where it will now flow onto portrait sections.