Thank you helena,
When it updates the order after each item removal, it updates only the last item changes in reality? The previous item removals have no effect because of the bad transaction? If you remove the items one by one, it works correctly, right?
Is that correct?
This is correct.
It updates only the last item as the transaction is committed at the really end, so the first item is not updated correctly.
If I want to remove items one by one there is no problem at all, but since there are at least 2 products to remove, there is a problem.
How can I manage to avoid this behaviour ?