Try to update the frimware on the rcmloader. The original website (xkit.xyz) is shut down earlier this year so you need to track down a copy of the firmware yourself. Btw almost all rcmloader you get on aliexpress/amazon/ebay/wish/etc. are clones of the original rcmloader, so the original firmware might not work for your device.
Iirc the file system used on the SPI flash chip is yaffs2, maybe you can manually format the chip yourself with arduino.