The part you are using has no built in flash, and in most circumstances is expected to be used with an external flash device connected via the LPC18xx's SPIFI interface.
Therefore the first thing to do is check how your project is configured - in particular whether you have configured your memory setup with an external flash device (and confirm that you have associated a flash driver). For more information, please see the MCUXpresso IDE v10.0.2 User Guide, section 12.8, "Using the Memory Configuration Editor". Also section 10.2.2, "SPIFI Flash Drivers"
If you are instead building your image to download and execute in RAM - then please see MCUXpresso IDE v10.0.2 User Guide, section 14.10, " RAM projects with LinkServer".
If you continue to experience problems, then please post your debug log - as described in the MCUXpresso IDE v10.0.2 User Guide, section 14.7, "The Console View" - along with a full description of how your project is configured.
Regards,
MCUXpresso IDE Support