Scope

The contact number XXX is already assigned to another contact. The contact number must be unique across all contacts.

Solution

Please check the contact in Xero, and collect the contact details- 

A. The internal ID of the contact in Xero: (Open the contact in Xero, and share the ID in the URL tab as highlighted in the screenshot below)



B. The corresponding Chargebee customer ID 

Send the details across to [email protected] and we will perform the mapping from the backend to map the Chargebee customer to the contact in Xero.