SMS provider carrier-specific degradation
At 19:20 new-user signups and 2FA logins start failing at the SMS step. Dashboards: your SMS provider's API for sending OTP codes returns elevated 500s and high latency for one route (carrier/region specific); login-completion rate for users requiring SMS 2FA drops sharply; users with app-based authenticator codes are unaffected. The provider's status page notes degraded delivery to certain carriers. Recent context: none on your side. How do you triage and mitigate?
What a strong answer looks like
Stop the bleeding first (mitigate), then form hypotheses from real signals. Separate root cause from symptom, communicate status as you go, and close with what prevents a repeat.
0:00 of about 30 min
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.
Run or narrate your approach, then ask the coach.