Almost every time, double-clicking the side button on my iPhone 16 Pro brings up my cards in Apple Pay immediately. Occasionally, though, the phone only locks and unlocks rapidly instead of opening Wallet. Pressing the button repeatedly can bring up the emergency SOS screen, and opening the Wallet app manually does not fix it. The shortcut only starts working again after restarting the phone, which is especially awkward when I'm trying to pay in a queue. I replaced my deteriorating case, but the problem happened again with the new one. I'm running iOS 26.6.1 in the UK, so I'm wondering whether this is an iOS, button-recognition, or card-provider issue.
2 Answers
This sounds more like iOS temporarily losing the Wallet shortcut than a problem with your bank or card. If the phone is clearly detecting both button presses but only locking and unlocking, the double-click gesture is being received but Wallet is not being launched. Check Settings > Wallet & Apple Pay and make sure double-clicking the side button is still enabled, then install any available iOS update. If it keeps happening, recording the exact time and checking whether Face ID or Wallet shows any error afterward could help Apple diagnose it.
A case or a slightly inconsistent click can cause missed double-presses, but that usually means Wallet opens intermittently—not that it stops working until a reboot. Since opening Wallet manually also fails during the problem, restarting is a reasonable temporary workaround. I’d also try force-closing Wallet, checking that the cards are still present and enabled, and contacting Apple Support if the issue continues, because the card provider generally would not affect whether the Wallet shortcut appears.

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