Duplicate Emails

I've been getting duplicates of all my emails since cox did some kind of upgrade.  I've read the forum entries on this subject but haven't found an answer that works for me.  The emails show up as duplicates in my on-line web-based cox account which are then pushed to all my devices which use both Outlook and other apps.  The issue is not Outlook or one of these apps it is at the cox end.  I have gone in to remove and reset any current filters, but had none to remove and reset. I only have this problem with one of my cox email addresses. How can I stop the duplications?