Okay, I have had this issue before and everything I have done to try and fix it this time is not working. I have recently added some new people to my contacts. I am receiving their messages on my Mac, but their name is not showing up on the message, just the phone number. The default account on my phone and Macs (I have two with this issue) is the iCloud account. On my MacBook Air, the newly added contacts aren't even showing up in the contacts app. I have signed in and out of iCloud, disabled the contact syncing and turned it back on, restarted my devices... nothing. Any idea what to do because it is driving me crazy not knowing who is texting me!