GST RCM error in 3B Return

Respected members

I need help in resolving an error made by accountant in GSTR 3B filing

Facts

1. Supplier is a sole trader rendering banking service and is subject to Reverse Charge
2. GSTR 1 correctly filed by ticking field "Supply attract reverse charge"
3. GSTR 3B error was made by manually punching Integrated tax amount in table 3.1(a)
4. on account of which they ended up paying tax 

Need help in resolving the above issue without affecting already issued invoices ( as issuing credit note will nullify earlier invoice issues and might create issue with service receiver)

Regards

Jayaram Prasad