iOS Zoho App and Native Mail App - Unable to verify account information

iOS Zoho App and Native Mail App - Unable to verify account information

I am using an iPhone 6 and wanted to get the iOS badge count for the Zoho mail app to see the amount of unread messages. However, this feature is currently unavailable so I wanted to switch to the native iOS application to for the badge count function. I tried following the Exchange sync instructions online and here http://zsync.zohosites.com/iPhone.html but the error "Unable to verify account information" shows up. I have two factor authentication activated and am using app specific passwords. Please help.