Line Item Attribute are not getting populated

Hello,

My requirement is to delete the existing Service Package and add a new Service Package  to a root Product.

I am able to achive this by Scripting.

My issue is, I am able to add the Service Package at the Line Item level and made sure its port Id is also getting populated by scripting only , but Line Item Attributes are not being populated for this newly created Service Package.

Apart from Port Id , is there any other field which we need to populated for Line Item Attribuite creation.

Please share if someone has any idea on this.

Thanks