Is there a way to populate multiple Delievery challah in Single invoice?

Is there a way to populate multiple Delievery challah in Single invoice?

Hi,

We are basically into IT services and give complete solution. Many times it happens that we send material on multiple delivery challans and raise a single invoice from all challans. We are using delivery challan and invoice only for our customer billing. We convert individual challan to invoices. Can we have a way to attach multiple delivery challans and raise a single invoice. this will and should problems for many companies.

Please develop this option.