Why won't my iphoto albums sync onto my iphone 6s?

Hello,

So I recently made four albums on my Macbook's iPhotos and now want to upload them onto my iPhone 6s. I connect my iPhone 6s through usb connection, iTunes opens up, I select the device and click on the photos tab, select sync photos, select my four photo albums I want uploaded to my iPhone 6s, and then the Sync button at the bottom. As expected my iTunes shows the "syncing onto iPhone" process at the top and then after it's complete, I check my iPhone and the albums are not there. What am I doing wrong?

Macbook macOS High Sierra Version 10.13.4

My iTunes is 12.7.4.76

My iPhone 6s Software is iOS 11.3.1

Thanks!

Kristin