It's a system partition.
Backup using SP Flash Tool V6 (from Mi Flash Pro Tool) by using Read Back and using mtkmeta utility for bypassing authentication file.
Install Microsoft visual C++ 2015 - 2022 Redistributable for SP Flash tool V6 to work.. RESTART PC AFTERWARDS
Install the libusb-win32.....driver and install the filter after setup by using your phone in BROM ( when power off, press and hold volume up and down together and connect USB to PC, Then you will see your phone detected on Filter installer wizard and select it and click install quickly as possible (within 3 seconds). other wise the phone is going to disconnect and boot back.
You also need to download the firmware and load the scatter file in to the SP Flash tool and Bypass authentication using MTKMETA Utility and go to read back to back up these Partitions in Img or bin format. USE Youtube for this purpose.
These are the partition of Poco M4 Pro 4G after losing IMEI and restoring it using DFT Pro. I formatted the phone afterwards and the IMEI was not permanent and it showed NVDATA corrupted and was not able to boot. These was the partition before getting the error. I did restore the partition and it showed the same error. Hope someone find it useful.... Use MI Flash Pro > SP flash tool V6 to restore.