1) Uninstall “Bluetooth GPS” app if you installed it (according to Garmin instructions). You do not need it with RaceChrono, and in fact it obstructs RaceChrono from directly connecting to your GPS receiver.
2) Make sure you have “Settings > Expert Settings > Bluetooth fix” disabled. If you enable it, your phone no longer connects to Garmin GLO.
3) You can try to reset the device by first turning it off. Then turn it on, by holding down the power button for 20 seconds. The receiver does a cold reboot.