This happens to me on occasion, and the only thing that works when it does is to completely unpair, and then go all the way back to the qr code pairing routine. That actually doesn't work either, and what I found is I have to shine a *really* bright light on the QR code for the phone to register it. Once it does, I can re-pair the phone. Sometimes takes a couple of tries to run through the whole process, but it works eventually.

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Tech writer/support on this here site. FIST school instructor and certified bike fitter. Formerly at Diamondback Bikes, LeMond Fitness, FSA, TiCycles, etc.
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