I've been having the same issue as described above. Have to touch ID twice and TAP TWICE to complete a purchase, even though the phone shows "done" after the initial tap.
A more serious problem is the transaction having gone through on the phone, with the terminal still waiting for payment. I ended up paying twice for the same purchase. This has happened to me a few times with both of my discover cards at different walgreens locations. I don't know if the pending auth will fall off or not after 10 days. I had the walgreens manager talk to discover over the phone and explain the situation, but discover insisted on requiring a "merchant ID" to remove the duplicate charge. Nobody at the store knew what it was.
I've always hated apple and their products, because they always gave me crap. If not for the discover promo, I would never have bought an iphone or used apple pay. Pain in the ass. You guys probably know how often touch id fails, due to slight variation in grip style and in region of contact of fingertip. One day I trimmed my nails and skins and the recorded figerprints immediately became useless, altuough I try to let it scan my entire thumb and even record more than one entry for a single thumb.
There is a guy on youtube who drove through mcdonalds and had the cashier pull out the terminal for him to tap the phone. So it actually could work, for those wondering....
