You need to boot twrp through fastboot, using
fastboot boot recovery-TWRP-3.4.2B-1206-XIAOMI10-CN-wzsx150.img
... and for those who do not have the TWRP above,
here is the link. This is for the
Mi 10 (umi).
But, DO REMEMBER - this is only for booting (temporary). DO NOT FLASH this version of TWRP.
This decrypts, and will work with a pattern, not code. It takes about 70 seconds to load up, and you have to click a few mms below the target.
Use the Fastboot command:
fastboot boot recovery-TWRP-3.4.2B-1206-XIAOMI10-CN-wzsx150.img
(as above).
However, if you are stuck in a loop from using the wrong TWRP, you can try flashing the following TWRP is
3.4.0 (LittleTurtle2333) - from GitHub
Use the Fastboot command:
fastboot flash recovery umi-3.4.0-11.0-1110.img
This puts this TWRP into the recovery partition - this is permanent, until replaced.
Do NOT confuse the two.