WhatsApp will soon let you verify your account via phone call
Verifying your device – Fetch
Device Verification – eGifter Support
Verification Required FAQ – Discord
Identity Verification – Grabr Help Center
Need to stop further verification on my Google account - Google Account Community
Why Can't I Verify My Phone Number for Apple ID?
Why Does ChatGPT Require Phone Number Verification? - ChatGPT Blog
multi factor - How does entering a phone number help Google verify it's me? - Information Security Stack Exchange