PLS HELP mistake in IISC Mtech application form

My friend actually submitted and had done payment but only entered EC and forgot to put IN cuz he thought its a seperate application. He said there was no option to add another gate score now. He emailed and called them but no response.

In short, is there anyway we can add another gate paper after payment
He actually got rank below 10 in IN and has good chance.
Thanks in advance