It says too many attempts. How long do I wait?

After 5 wrong attempts on the same address, each further try has to wait. The wait starts at 30 seconds and grows up to 15 minutes.

The page tells you how long is left. Waiting is one way out; resetting your password is the other, and it clears the backoff immediately.

The count is against the address that was typed, not against your device, so it applies whether or not that address has an account. That is deliberate: it stops the delay from revealing which addresses are registered.

If this did not answer it: support inside your account is under development, and until it opens, this says what does reach a person.