I had a similar experience with my Xiaomi (robotic) vacuum cleaner. A few days after setting-up a tor relay (not an exit node!) on my home connection, my vacuum stopped working. The "Mi Home" app, which communicates with the vacuum via a server in China, was unable to find the vacuum.

A traceroute to the Xiaomi servers revealed that my packets were dropped somewhere in the ChinaNet AS. I stopped my relay and everything went back to the normal a few days later.