Cannot sync Facebook contacts to Android Calendar (android 6.01)

[asystole420]

After clearing facebooks data/cache to free up some space, my phone un-sync'ed facebook with my calendar on my Note 4 with android 6.01 and now I am unable to re-sync it. When going to 'Accounts' then 'Facebook' it says that 'sync is turned off' but there is no way to enable it. further down, you can click on "sync with your device" but the box there is already enabled. If I unclick it, then re-click.. it seems like Google should prompt me with the 'Facebook wishes to access various things' prompt, but never does. Can anyone help me with possibly finding where on the phone you can manually go to give things permissions without being prompted? thanks.