error while inserting new records in contract entity

We are inserting new Customer information from Salesforce CRM to Microsft DCRM in Contract entity .
While inserting new records , we are getting an error message "The attribute type Customer of field billingcustomerid is not supported".
I am passing default value of '475B158C-541C-E511-80D3-3863BB347BA8' for column billingcustomerid and i have set the data type as Guid .
I took value of billingcustomerid from DCRM
I am still now able to fix this issue . Can some one be please help me in this reagrd . Thanks