Error while posting sales order packing slip

You are calling the inventJournalTrans.insert() twice. Remove the first call.

Hi Kranthi,

Still I’m facing same issue .Cannot create a record in Inventory journal lines tax extension (InventJournalTransTaxExtensionIN). Reference: 5639640603, 197CBE_GSTIN.
The record already exists.

Now which method is calling the insert? Can you show the call stack?

[s] \Data Dictionary\Tables\InventJournalTransTaxExtensionIN\Methods\insert 5
[s] \Data Dictionary\Maps\SysExtensionSerializerMap\Methods\postInsert 100
[s] \Data Dictionary\Tables\InventJournalTrans\Methods\insert 41
[s] \Classes\SalesPackingSlipJournalPost\endPost 135
[s] \Classes\FormletterJournalPost\post 294
[s] \Classes\FormletterJournalPost\run 11
[s] \Classes\FormletterService\postJournal 42
[s] \Classes\FormletterService\run 80
[s] \Classes\FormletterService\postSalesOrderPackingSlip 14

Does the insert() of this table called only once?

yes it is called only once, after changing the code suggested by you.

If it is called once, then why it would throw an error.

Have you tried to see if there is a data issue in InventJournalTransTaxExtensionIN?