Folks,

Referring to the original topic and the error message shared by the User

"The customer associated to this record is not linked to module chosen in the current contact sync configuration."

This error can occur due to one of the following reasons:

1. The record associated with the Invoice (such as the contact or account) might have encountered an error during the current sync attempt.
2. The record might have synced with another module based on the previous sync configuration (if any) Let's say, if the initial sync type was contacts only and then moved to Accounts and their contacts sync, the contact/account in the invoice would have been linked to the old module (Contacts)
   

To resolve this, you'll need to identify and remove any error records, and then set an instant sync for the respective module.

Regarding the second error message:

Module change for contact sync is not supported for two way integration. Please contact support.india@zohobooks.com for assistance.

This is an account-specific issue so we do have a general solution to share it here. We recommend users reach to out to support directly as it may involve specific configuration details unique to your Account.