Hello,
I understand why you get duplicates. As you may be aware, J2Store products has a Joomla content associated with it. To update this Joomla content CSVI uses alias and catid field and not just alias. Since your catid field is different from what is in database, CSVI creates a new Joomla article and so a new J2Store product has been added.
If you are looking at updating only catid then you can use
CSVI custom table import. In your custom table import template on Options tab set Custom table to be
content and import based on field to be alias. You can then use alias and your new catid in your import file and update you catids. Let me know if that helps.
Kind regards,
Tharuna
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