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.
Author
Notilify Team
The Notilify team writes practical notes for engineers and founders building OTPs, alerts, and transactional messaging into production apps.
Posts by Notilify Team
Why OTP SMS Fails in One Country but Works Elsewhere
Debug OTP SMS failures isolated to one market by checking route type, sender and template alignment, local registration, phone formatting, and delivery evidence.
SMS Sender Registration Failed: What to Check
Fix SMS sender registration failures by checking business identity, use case, consent, sample messages, templates, and number associations.
SMS Failing in One Country or on One Carrier
Debug SMS failures isolated to one country or carrier by separating number, sender, content, route, and downstream-network issues.
SMS Accepted but Not Delivered: Where the Message Failed
An accepted SMS request can still fail downstream. Isolate sender, content, registration, route, carrier, and recipient failures without retrying blindly.
SMS Support Runbook for Failed Account Alerts
Give support teams a clear runbook for failed account alerts, OTPs, delivery notifications, and security-critical SMS messages.
SMS Webhook Payload Examples for Delivery Tracking
Review SMS webhook payload examples for accepted, sent, delivered, failed, expired, duplicate, and out-of-order delivery events.
How to Debug SMS Delivery by Country and Carrier
Use country, carrier, sender identity, route, and webhook evidence to debug SMS delivery failures without guessing.
SMS Delivered vs Sent vs Accepted: Status Meaning
Learn what SMS accepted, sent, delivered, delivery completed, failed, expired, and unknown mean before building status callbacks.
Why OTP SMS Codes Do Not Arrive
Learn why OTP SMS codes fail, delay, expire, or never reach users, and how to debug verification delivery without guessing.
Sender ID Registration Guide
A scheduled guide for sender identity requirements, approval workflows, and country-specific sender ID expectations.
Transactional SMS API: Send Account Alerts, OTPs, and Track Delivery
Send OTPs, account alerts, and product notifications with a transactional SMS API built for delivery tracking, webhooks, and audit trails.
OTP SMS Delivery Best Practices: Test Delivery and Fix Delays
Test OTP SMS delivery with resend windows, fallback methods, rate limits, anti-abuse controls, templates, and delivery tracking.
Reliable SMS Webhooks and Status Callbacks by Country
Compare SMS APIs for reliable delivery webhooks, status callbacks, retry behavior, and country-level delivery tracking in countries like Spain.