It's a good idea to check the jumpers settings as Converse mentioned.
Additionally, from the error message you are seeing it would appear as if the debug firmware was either erased or corrupted. You can flash this firmware easily using the LPCScrypt tool (available in the link below).
https://www.nxp.com/design/microcontrollers-developer-resources/lpc-microcontroller-utilities/lpcscr...
Once installed in your host computer, please follow these steps:
Force DFU boot on your board. This can be achieved by placing a jumper in JP5.
Connect the USB Debug port to the computer.
Open a terminal and run:
<LPCScrypt Install Dir>\scripts\program_JLINK
Or
<LPCScrypt Install Dir>\scripts\program_CMSIS
Depending on whether you wish to use JLINK or CMSIS. (Both work with MCUXpresso SDK)
(C:\nxp\LPCScrypt_2.0.0_831\ is the default installation path of the latest version of LPCScrypt for Windows 10)
The LPCScrypt tool will then connect to the board and program the firmware. Once it’s done quit the tool using CTRL+C.
You may then disconnect the board, take out the JP5 jumper (optionally), and try debugging again.
I hope that this information helps.
Regards,
Gustavo