In ERP partially billed but in CRM billing status is completed

Hi All,

In ERP based on billing plan monthly like below screen, we have done the partially billing until 01.12.2013. when I checked in CRM on item level the billing status is set to completed automatically.

Below screen shot from ERP.

Below screen shot from CRM..

Any one have idea how to set the billing status is set partially completed or same status like ERP.

Thanks,

Preddy.