Reference details are not populated in PL_ELIXIR-O (Poland), when payment is made for net.

Hello Friends - We are using format tree – PL_ELIXIR-O (Poland). When we make payment for single invoice, Reference of this invoice is populated in payment file successfully and when we do the same for paying net of multiple invoices, Reference details are not populated in the file and shown Blank (Payment details note in format tree - PL_ELIXIR-O (Poland).

Can you pls check and let us know as to how to fix this.

Thanks