Flipsky 75100 - Flux linkage detection failed

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Does the motor offer resistance when you turn it by hand? If yes, one or more of the phases is shorted out, probably because of overcurrent while the chain got stuck.

Flux linkage detection failed (Motor detection)

spin resistance just means that there is a short somewhere in the phase wires. If the short isn’t external, then the ESC fets are blown in open, essentially same thing as a short circuit. If the motor spun fine before you ran motor detection and it only happened after, then it could’ve been caused by a short during motor detection. If it was like that before you ever powered on the ESC, then it was defective from factory.