Carrier-Rejected SMS: An Incident Runbook
Use this incident runbook to isolate carrier_rejected SMS failures by sender, route, country, carrier, template, and recipient without causing retry storms.
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The Notilify team writes practical notes for engineers and founders building OTPs, alerts, and transactional messaging into production apps.
Use this incident runbook to isolate carrier_rejected SMS failures by sender, route, country, carrier, template, and recipient without causing retry storms.
Debug OTP SMS failures isolated to one market by checking route type, sender and template alignment, local registration, phone formatting, and delivery evidence.
Fix SMS sender registration failures by checking business identity, use case, consent, sample messages, templates, and number associations.
Debug SMS failures isolated to one country or carrier by separating number, sender, content, route, and downstream-network issues.
An accepted SMS request can still fail downstream. Isolate sender, content, registration, route, carrier, and recipient failures without retrying blindly.
Give support teams a clear runbook for failed account alerts, OTPs, delivery notifications, and security-critical SMS messages.
Review SMS webhook payload examples for accepted, sent, delivered, failed, expired, duplicate, and out-of-order delivery events.
Use country, carrier, sender identity, route, and webhook evidence to debug SMS delivery failures without guessing.
Learn what SMS accepted, sent, delivered, delivery completed, failed, expired, and unknown mean before building status callbacks.
Learn why OTP SMS codes fail, delay, expire, or never reach users, and how to debug verification delivery without guessing.
A scheduled guide for sender identity requirements, approval workflows, and country-specific sender ID expectations.
Send OTPs, account alerts, and product notifications with a transactional SMS API built for delivery tracking, webhooks, and audit trails.
Test OTP SMS delivery with resend windows, fallback methods, rate limits, anti-abuse controls, templates, and delivery tracking.
Compare SMS APIs for reliable delivery webhooks, status callbacks, retry behavior, and country-level delivery tracking in countries like Spain.