Hello,
I do not think there is a way to reset your registration as you are already a registered candidate. As you have mentioned your query you can use your previous credentials to apply for round 2 and there you can choose your preferences. And I also do not think that you need to pay again. I hope this would work otherwise if you want to register as a fresh candidate then you would have to forfeit your security money.
Hope it helps.
Good luck.
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