The BOND is the best way I’ve found to control my DC fans. Only problem is that the only supported ways to control the BOND is through their app, Alexa, or Google Assistant, no third-party integrations with any other home automation systems or public API docs. I’ve reached out to support a few times…

BOND Fan Control Unofficial API Docs

codypet2002 (Codypet) May 28, 2019, 3:54am 14

This is related. Sounds like Mqtt breaks whenever you locally try to control a fan.