Hi Sagar Prajapati ,
About the RT problems, you can try to erase the internal flash, please refer to the following picture: 
If you still can't make it work, you can change the BOOT_MODE to serial download mode, then do the erase memory again.
BTW, JLINK commander also can do mass erase:

Wish it helps you!
If you still have the pure RT questions, welcome to go to RT forum and post your RT question:
i.MX RT
Have a great day,
Kerry
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