Photos on Mac Not Recognizing Faces

Faces not being recognised in photo app on mac

I am trying to get photos to recognise faces like it used to. It seems to have stopped working some time ago. Even though on my iphone the faces are recognised. I can see on icloud all photos are there. I have tried doing the option command when photos opens to restore the library, that didnt work and got rid of all the photos I had manually added. If anyone could help it would be appreciated.