@Abdou1 .
Now that is sorted (IsBlank had no purpose), you can do this - firstly, I assume you selected the original item from a gallery ? If so, you can get both IDs
Set(
gblOldID,
YourGalleryName.Selected.ID
);
Set(
gblNewID,
Patch(
'Demande Capex';
Defaults('Demande Capex');
Form4.Updates
).ID
)
Now do a Flow and send both IDs - if you are now familiar with Power Automate, this may be difficult for you

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