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How Carrier Lookup Blocks Your AI Agent's Phone Number
Every OTP service runs a carrier lookup before sending verification codes. If your number returns 'VoIP', the code is never sent. Here's how it works and how to check.
Fix: WhatsApp 'Unsupported phone numbers such as VoIP' for AI Agents
Solve WhatsApp Business API registration errors. Learn why WhatsApp blocks VoIP and how real SIM numbers enable agent registration.
VoIP vs Real SIM: Why Your AI Agent's Phone Number Gets Blocked
Deep technical comparison of VoIP and real SIM numbers. LERG/NPAC database analysis and which services block VoIP.
Fix: Stripe 'This phone number cannot be used' for AI Agents
Solve Stripe phone verification errors for AI agents. Learn about carrier lookup, VoIP blocking, and how to use real SIM numbers that pass verification.
The Complete Guide to Phone Verification for AI Agents in 2026
Everything you need to know about phone verification for AI agents. Compare all approaches and find the right solution.
Why Your AI Agent's Phone Number Gets Blocked (And How to Fix It)
A technical deep-dive into carrier lookup APIs, LERG/NPAC/OCN databases, VoIP classification, and how to get a real mobile number your agent can actually use for SMS verification.