I am using Magento 2.3.4 which was recently upgraded from Magento 2.1.15. Currently i am facing an issue with product qty after duplicating products.
After duplicating the original product P1, I get P2 with the same quantity P1 originally had. But after P2 got duplicated from P1 the original qty of P1 is getting changed to Null.The Quantity field is empty when i view the product from admin panel.
I did re-indexing but still the stock did not update. The indexer are set to "Update on Save" .
I tried the below step from the link
But this also did not help.
I also noticed that the original product is removed from the cataloginventory_stock_status table after i perform a full re-index.