Your import stops and displays this error:
You are trying to add quantities to a product with combinations: product ID_X
This error occurs only when the Advanced Stock Management is enabled on products/combinations.
When a product has combinations, quantities are managed on combinations only - the parent product show the total quantity of all its combinations and its quantity field is not editable.
Therefore, if you get this error during your import, this means that the line generating this error correspond to a product onto which the quantity needs to be updated, but that product has combinations ==> quantities cannot be modified on a parent product that has combinations
You'll need to download the TODO file to check what is that product, and modify your file accordingly.
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