Hello,
1.
Which app are you using, F&O, Finance or another one?
The following comments hold for F&O
2.
We are updating the financial dimension through Excel-Add in standard entity and it works. Therefore, I would ask you for some more information, screenshot about the validation you mentioned.
3.
Changing the fin. dimension on the header works differently when you do it in the application vs the excel add-in, i.e. entity.
Generally, when you put in\change something in a header form, these information is being replicated to the lines, which means, it works when you create new lines, but does not work on existing lines. Therefore, MS implemented the dialog that updates the lines when you update the header information.
However, that business logic\dialog works when you update it in the application, but not when you update it through the entity, i.e. the excel add-in or any other api.
I would suggest 2 approaches:
1. Check if excel add-in works, hence share some more information as I mentioned. Keep in mind, even if it works with excel add-in, you need to do it on every PO, depending how many POs you have, this might not be the best solution.
2. There are custom scripts that run database queries that can update data. Its a solution for correcting\updating data, exactly your scenario.
Hope this helps,
Adis
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