This is the most recommended action. Unfortunately it is not a solution.
I don't have this problem and I synchronise both mine and my wife's outlook calendars to our phones. However, it strikes me that this might be caused by a mismatch of time zones somewhere along the line. I suggest that you check that Office 365 and your phone are set to be in the same time zone (though if this is the case and you correct it, it may screw up your currently correct entries).