Unsuccessful pairing will be indicated in the Hailie™ app.
If paring is unsuccessful please follow the Hailie™ app instructions and try pairing again. Check that the Hailie™ sensor battery level is good. Go to How do I find out what the battery level is on my Hailie™ sensor?' to check battery level.
If the serial number of your Hailie™ sensor does appear in Setup list when you search for your Hailie™ sensor, try to Forget This Device in your phone/tablets Settings menu before attempting to re-pair.