Cant access my iCloud photos from my iPhone

My wife uploaded 5900 photos to icloud since her phone ran out of space. Since doing that, she has been unable to access her photo library from her iPhone. She has 200gb of cloud storage and 32 gb on the phone itself.

In Settings the iCloud Photo Library, Ulpoad to photo stream and photo sharing are turned on. Download and keep originals is checked.

How can she access her entire iCloud photo library from the phone rather than only via a PC??