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The code never arrives

• Wait a minute, then check spam and any filtered mail tab.
• Confirm the address. Tap Use a different email and type it again slowly.
• Request a new code. Issuing a new one invalidates the previous one.
• If you request several in a row you may be asked to wait before the next.

The code is refused

• Codes expire. Use the newest email, not one from ten minutes ago.
• Each code works once. If you already used it, ask for another.
• Check for a typo. Six digits, no spaces.

Two factor is in the way

Enter a code from your authenticator app, or one of your recovery codes. Recovery codes work once each.

Lost both? Write to support@k00l.app from the account email address.

The account is suspended

That is a moderation decision, not a bug. See How moderation works, and how to appeal.