Is this the Samsung or the Google Calendar app?
by R. Proffitt - 3/21/13 11:12 AM
In Reply to: Calendar Apps Sync Problems (Galaxy S) -- Fix Needed! by WDC200236
I shouldn't write this but will. I tend to eject/not use any maker's apps. They usually have issues and right or wrong I rarely see such fixed.
My advice is to use another calendar.