Outlook / Zoho Contact Sync Issue

Outlook / Zoho Contact Sync Issue

I have an issue where I am only syncing from Outlook to Zoho but the sync reverts after a while back to having Zoho sync with Outlook.  This creates duplicates in Outlook adding duplicate contacts because it puts them in a category labeled Zoho and applying a purple label to them.  So there are two issues:  1)  the reverting from Outlook to Zoho back to Zoho/Outlook and 2) the duplicate label.  
If we can cure the duplicate label I would be fine with sync both ways.