Business partner with GUID XXX does not exist

Dear All,

I am trying to replicate r/3 customers to crm, however all customers are not getting updated in CRM. I checked SMW01 for the customers not uploaded. There is an error message as

"....Business partner with GUID XXX doe not exist

Validation error occurred: Module CRM_BUPA_MAIN_VAL, BDoc type BUPA_MAIN...."

pl. let me know the solution on how to rectify this error.

Thanking you,

Regards