Hello CathyFe,
and welcome to this Apple (user-to-user) Community!
Re: "How to require double tapping of passcode numbers with Voiceover on?"
" ... with my new 17e, even with Voiceover on it selects numbers as soon as they are touched, making it impossible for me to use my passcode independently."
Wondering whether or not your iPhone is updated to the newest version of iOS 26.
(Updates often include bug-fixes, and much more.)
You can check in Settings > General > Software updates.
Reminder: It is wise to back-up iPhone first iif you choose to update iOS.
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Thank you for your question: Am no expert in this area. The experts are mostly people like yourself who use VoiceOver quite a lot. Yet your post deserves some response.
From what I found:
Seems we can now use a simpler method to enter a passcode in iOS 26:
Whether or not that private method will help, only you will know.
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For iOS 26: Operate iPhone when VoiceOver is on - Apple Support
Eg: says:
Unlock iPhone
- On an iPhone with Face ID: Wake iPhone and glance at it, then drag up from the bottom edge of the screen until you feel a vibration or hear two rising tones.
- On an iPhone with Touch ID: Press the Home button using the finger you registered with Touch ID.
If prompted, enter your passcode. To avoid having your passcode spoken as you enter it, enter your passcode silently using handwriting mode or type onscreen braille.
Eg: says:"
- On the passcode screen, set the rotor to Handwriting.
- Write the characters of your passcode with your finger."
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Re: "Does anyone know which to change in Settings in order to require double tapping of each number?"
The experts in Apple Support's Accessibility support team may, or may not know.
You can reach out to them for help with any accessibility feature, like Voice Over, if you wish:
See:How to contact Apple for help with accessibility features - Apple Support
All the best :-)