I think you are talking about the JOSAA counselling based on JEE MAINS and JEE ADVANCED ranks.So,there are only seven rounds in counselling.And after 7th round you can get a seat under spot counselling in which you will have to physically report to the institute.Also to take part in spot round you will have to pay fee to take part in this round which will be adjusted in college fee once you will be alloted a seat.But you can get only lower ranked and not much popular branch under this.So,keep that in mind.

Hope this helps.