GST Invoice Amendment - Query

I have two invoices from the tax period of May 2025 that need to be amended in the July 2025 return.

• For both invoices, I need to correct the invoice numbers.

• Additionally, for one of the invoices:

  • The original invoice date was entered as 30 May 2025, but the supply actually pertains to 30 April 2025.

  • The GST rate was incorrectly reported as 18%, whereas it should have been 0%.

My questions are:

1. Is it sufficient to report these corrections under the B2B amendment table in the GSTR-1 for July 2025?

2. Since the GST rate is being changed, do I also need to issue and report a credit note for the same invoice?