OTP SMS: delayed or missing when roaming or on VoLTE

On some MVNOs or roaming, SMS to short codes is deprioritised. VoLTE and Wi‑Fi calling can also delay inline SMS handoff.

Wait the full 120 seconds before a second request; rapid retries can trigger throttling. Move to a known UAE carrier SIM or Wi‑Fi without tunnel if you only need a one-off OTP.

Disable “Wi-Fi calling” and test again on full mobile data. In phone settings, ensure premium SMS/shortcode delivery is not blocked. If the portal offers email OTP, switch channels temporarily.

For repeated failures, note time zone, carrier, and last four digits of the number—support teams can correlate with SMS gateway logs.