How to avoid doubling of Issue of Material on the Tech Portal and also on the Charges lines

We want our service Invoices to have the main Item (Finished Good) and the Materials used. We are generating WIP jobs from the Technician Portal and the system makes us to compulsorily Issue Materials before we can Complete Work. But, if we want the Materials to be shown in the Invoice lines along with the Finished Good, the Materials need to be submitted to Order Management as well. Which means, the Materials will be transacted again (after already being transacted from the Tech Portal).

How do we overcome this double-transacting of the materials? If we don’t submit the Materials to OM processing from Charges lines, the Sales Order will not contain these Material Lines and so the Invoice will not have these Materials.