Unfortunately I'm not on AT&T's network to see if it's an issue on their side. But if you updated your phone yesterday, that might be what's causing it. Do you have another work account you could add? Maybe ask a friend at work to let you add their account just for testing, and then deleting all the data. This would check to see if it's an issue with any syncs or just existing ones. IF the new account syncs, what I'd suggest is to remove your accounts, reboot, and add them again (yes, I know it's a PITA setting things back to the way you liked them and it's going to consume data syncing, but if that makes it work again...)
PS: Check your date/time settings. If they're not set to the correct date, sync can run into a lot of undisclosed issues.