Shekhar your query is incomplete. Please elaborate about which college's registration link you are talking about and on which page the link you have checked is not working then only we will help you in a better way and try our best to connect you with the correct link so you can continue your registration process.

If by KGP you mean IIT Kharagpur and you are looking for M.Tech admission then you can use this link: https://gate.iitkgp.ac.in

Feel free to ask if you have any more queries. All the best!!