DRC-03 interest paid under CGST/SGST instead of IGST - how to rectify?

I paid interest for a past period (omitted supplies) through DRC-03 under CGST and SGST (Rs 7,461 each), but the interest was actually due under IGST because the tax was mainly IGST. IGST interest was not paid at all.

What is the correct way to rectify this?

1. Can the CGST/SGST interest be adjusted against the IGST interest?
2. Or do I pay IGST interest again (through GSTR-3B Table 5.1) and claim refund of the CGST/SGST interest later? Which refund route and time limit?

Thanks.