Incorrect HSN code in invoice and gstr1 file

This discussion addresses the issue of an incorrect HSN code being used on an invoice and subsequently filed in GSTR1. The user has submitted their return but wishes to correct the HSN code without altering dates or amounts, and no e-way bill was generated. Advice is sought on how to amend the invoice and GSTR1 filing, and whether any penalties apply, especially as no official notices have been received yet.