PI ESR mapping issue with multiple line items

Hello Gurus,

I have an issue with PI mapping that keeps failing 'Cannot create target element' when I have multiple line items. However, the same mapping works with only single line item. I have provided the screenshot for the issue. My header occurrences is 1: unbound and Item is also 1:unbound. Also 1 header record can have nulitple line items.

Thanks in advance for your inputs and help.