Show if - Only related Table has specific Status/Value

[pricetag]

Hi, I'm having trouble creating a show condition.
I have orders (table orders) - open & closed.
The orders have related order entries (table order summaries)

I only want to display the "Add" action (which adds entries to the order summaries) if the associated order is not completed ([Status] "Open")

The problem seems to me that the relationship to the order only occurs when the entry is created.
Can I create this condition if

Order [Status] = Open - then Show "Add"

I've tried many conditions, unfortunately it either always shows me add or never

Thank you!

[Suvrutt_Gurjar]

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