I have allowed seat in round 2 I have for got upload documents  then what I can do

Yes you need to pay the seat acceptance fee as well as upload documents after accepting/Floating the current allotted seat.

Subsequently you do not need to again pay anything and the fee is adjusted, incase you get another allotment in later rounds.

Next would probably be your Institute fee payment post Last Round of Counselling and your final Allotment. All the best.

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