If you have recently used Telegram on another device, the login code is sent inside Telegram rather than by SMS. Check any device where you are still signed in, and look for the chat with Telegram, a verified account with a blue check.
Where to look
- Open Telegram on a device that is still signed in. Another app on the same device also counts.
- Find the chat named Telegram with the blue verification check.
- The code is in the most recent message there.
No SMS will arrive in this case, so waiting for one is the mistake to avoid. It is also why the code can seem to have vanished when it was delivered promptly.
Why it works this way
A code delivered through an already-authenticated session is more secure than a text message. SMS can be intercepted, redirected through the carrier or read from a lock screen. A message inside Telegram requires an existing signed-in session, which an attacker holding only your number does not have.
Never pass the code on
The code logs somebody into your account. Telegram staff will never ask for it, and no support agent, giveaway, verification process or friend in trouble has a legitimate reason to need it. Anyone requesting your login code is taking your account, without exception. The most common version of this scam is a message from a compromised friend asking you to forward a code that "was sent to you by mistake".
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