Exchange Calendar Syncing!

On my microsoft exchange calendar I have my own calendar and the shared calendar of 5 colleagues.

I have successfully synced my entire exchange calendar to my iphone IOS calendar.

Frustratingly however the IOS calendar is only showing the calendar of one of my colleagues but not the rest of my calendars (including my own).

I have checked the calendar settings and ensured that all exchange calendars are selected (show all) but still it only shows me one of my 6 exchange calendars.

I have tried deleting the exchange account from my iphone and relogging into it and I have also tried toggling the calendar sync on and off but none of this has worked.

Please help.