If you generate an IRN for an e-Invoice in the IRP, you should manually update it in the corresponding e-Invoice in Zoho Books. To do this:
Note:Within the first 2 days of pushing an invoice, you can retrieve the acknowledgement number and date from the IRP portal by entering the IRN. After this period, please refer to the GST Portal for this information.
Now, your IRN generated in the IRP will be associated with the invoice in Zoho Books.
Books
Simplify accounting
and GST filing.