Dear student,

You have been given 3 chances of JEE Mains and 2 chances of JEE Advanced . JEE Mains is conducted twice a year. So, overall 6 chances are available. If you have have accepted a seat in some IIT, then there is no worry. You can again give JEE Mains the next year. But make sure that your chances are left. And you are talking to take IITB then it means you also have to give JEE Advance in the next yeat. So, also make sure of JEE Advance chances, whether they are left or not.

Hope this helps.