When SMS doesn’t arrive on the platform, fix service → acceptance → formatting → swap before assuming a total outage.

Checklist
| Symptom | Likely cause | Fix |
|---|---|---|
| No SMS ever | Wrong service | Re-order correct app/service |
| Number rejected | Virtual / burned | Real SIM or other country |
| Invalid format | Double country code | National digits only |
| Timer empty | Dead line | Cancel and swap |
| Waiting on call | SMS-only line | Choose Send SMS |
Also: Why SMS platform not receiving code.
Wrap-up
Swap beats waiting. Most “no SMS” cases are mismatch or burned stock.