DIAGNOSIS Bluetooth pairing issues are super common. The fryer's signal isn't strong, and it times out quickly.
FIX Make sure your phone's Bluetooth is on and you've granted the Cosori app location permissions (weird, but needed on Android). Unplug the fryer for 30 seconds, then plug it in. Immediately open the app and start the pairing process. Hold your phone right next to the fryer (within 3 feet). Don't touch the fryer controls during setup.
IF THAT DIDN'T WORK Delete the Cosori app, restart your phone, reinstall the app, and try again. Also, make sure you don't have any other Bluetooth devices actively pairing at the same time.
HEADS UP The Bluetooth is only for setup and sending recipes. You can't control the fryer remotely while cooking—it's not a live connection. So if pairing fails, you can still use all functions just fine.