Hello Yash,
Could you please try unlocking your LPC board with the following guide?
First, could you please download and install the latest LPCScrypt version from our website and the latest J-Link Software and Documentation pack from the Segger website.
Install them, and then please try reinstalling the included drivers in the "Drivers" folder in your install location (by default it should be C:\nxp\LPCScrypt_2.1.0_842). After doing that, please go into the scripts folder and launch the "program_JLINK.cmd" script.
On your board, please make sure the DFU link jumper (JP5) is shorted, and then connect your board, then press any key. Your board will now have Jlink installed. Remove the DFU Link jumper (JP5) and restart your board.

After doing that, launch Jlink Commander and type unlock LPC5460x:

After doing that, try connecting to the device by typing "connect", pressing enter and selecting SWD as the Target Interface, and after pressing enter one more time you should see something similar to the following screenshot:

Best regards,
Sebastian