Messages / iMessage on Mac and iPhone not working together

I am logged into Messages (iMessage) on my Mac and my iPhone with my Apple ID, and I have all boxes checked (phone number and emails) to send/receive messages. I have given my phone "permission" with a code to sync and push messages to my Mac, but for some reason it is still not syncing. I have tried logging out of both and logging back in, and nothing seems to work.

How do I fix this problem?

On my Mac I am running OS X Yosemite 10.10.3 and on my iPhone I am running iOS 8.4.