How do I resolve a "This number is not usable for authentication" or "cannot be added" error when enrolling a phone number?
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Instagram asks me to verify my phone number, but I'm unable to get a verification code. What should I do? - Quora
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Google Play Store Account Fix This Phone number format is not recognised. Please check Problem solve - YouTube
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Dutch data-only phone numbers are not recognized as valid · Issue #9005 · signalapp/Signal-Android · GitHub
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Not able to call my number. Error: "The number you have called is not recognized" | Join the discussion, ask questions, share advice.
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Unable To Add Phone Number That Needed For Register Twitter API Developer Account - "Please enter a valid phone number" Error - Twitter API v2 - X Developers
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