Zoho Subscription Sync to Zoho CRM

Zoho Subscription Sync to Zoho CRM

When Zoho Subscription is sync (settings / integration / zoho apps / zoho crm)
(Sync Both Way Activated - Accounts & Contacts - Overwrite checked)

If a contact person was already existing as a contact in Zoho CRM.
The sync generates a Duplicate in Zoho CRM!

The overwrite option just works to avoir duplicates in Zoho Subscription.
But do not work to avoid duplicates in Zoho CRM.

No chance to get a Workaround?
Or a fix ?