Hi,
As explained before, you have two options in case of unplanned delivery cost - Either to activate "distribute to calculated invoice items" or post to seeperate GL"
If you are adopting the first option, you can give the unplanned delivery cost in the GL account tab in MIRO with relevant sertvice tax tax code. Please see below the details.
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If you are adopting option 2, ie seperate GL, you can give the unplanned delivery cost and the respective tax code in MIRO Header- Details tab as explained in my previous comment.
Hope its clear and helpful.
Regards,
AKPT