I have tried connecting my yeelight strip to my house wifi and the connection keep timing out. Also I tried connecting via SG & China server & both does not work with the yeelight app and the Mi Home app.
However , it works I connected it via my personal hotspot it works since then I updated the firmware to the latest and tried to contact back to my house wifi but still not able too.
Check my router log and it seem like its not able to get a IP address from my router.
Phone used: Nexus 6P (Android 7.1.1) & Sony Z5 Premium (Android 6.0.1)
Yeelight Mac: 286C0772362B
Xiaomi account: 573561015