Hello there,
If you don't pay your admission fees by the mentioned last date, then it may get cancelled, unless the last date is extended. You should pay your fees within the time given to avoid any kind of hassle. In case you are facing some financial issues, and cannot pay the fees within the last date, then it is suggested that you speak to the college authorities to get a solution by mutual understanding. It's better if you contact them if you are facing some difficulties, else your admission may be cancelled.
Hope this answer helps you.
Thank you!!