Reminders not syncing between OSX 10.10 and iOS 8

I have followed all of the troubleshooting steps from Apple to no avail: Get help using Reminders in iCloud - Apple Support

I opened Reminders on the Mac and added 7 items to a list. None of them have showed up on my iPhone (after 3 days of troubleshooting etc.)

I opened Reminders on the iPhone and added 5 items to the list (which was empty; none of the items entered on the Mac were there, and they weren't completed/hidden; again, the syncing still hasn't happened after 3 days of troubleshooting).

Neither the items entered on the Mac or the items entered in the iPhone have synced: I have one list on my Mac and a separate list on by phone.

Ideas?