We use the icloud to syn multiple calendars on multiple phones. They are no longer syncing. Any ideas.

Make sure you are signed into the same iCloud account on all of them in Settings>iCloud with Calendars turned on. Also make sure you are adding events to your iCloud calendar. Go to Settings>Mail,Contacts,Calendars>Default Calendar ( in the Calendars section) on each of your devices and make sure you have selected your iCloud calendar as your default, and not something else like On My iPhone, Google, Yahoo or Exchange. After adjusting your settings, add a test event on each of your devices and confirm that your calendars are syncing properly now.