Adding asset to existing capitalized or CIP Asset using Asset Integrator

Hello Experts,

My requirement is to add new asset lines to the already existing assets. For this I am using Asset Integrator (WEB ADI) .

As I need to do addition for existing asset, in the WEB ADI template I am putting the same (existing) asset number with all the other details like category, location, expense account etc. as per existing asset assignment. But my upload is rejecting lines with reason "This Asset Number is already in use. Please enter another."

Can you please guide me on how do we perform addition to already capitalized asset using integrator/WebADi template.

I appreciate your help.