Since you have a NPAT rank of three thousand eight hundred fifteen and you have been offered a seat at the Navi Mumbai campus while being waitlisted for the Mumbai campus it means you have a confirmed admission in Navi Mumbai but you must decide if you want to stay on the waitlist for the Mumbai campus You can accept the Navi Mumbai seat now and pay the required fees to secure your spot Do keep your waitlist active by following the Mumbai campus instructions such as paying a nominal fee or confirming your interest If a seat opens up at Mumbai you will be considered in further rounds If Mumbai remains your top choice you should keep checking the admission portal regularly and respond promptly when a seat becomes available Remember to read the guidelines carefully for acceptance and waitlist procedures To summarize you can go ahead with Navi Mumbai admission and stay on the Mumbai waitlist simultaneously until final seat confirmation