"This account has moved to a new phone twice in the last 30 days. Sign out on another phone first, or try again later."
Signing in on a new phone can sign out the one used least recently, but only twice in 30 days. The limit stops an account from being passed around between people; changing your own phone is never a problem.
What to do:
- Sign out on a phone you don't use any more (in 1krNote: Account → Logout), or remove it on the website under Phones. A free place doesn't count against the limit: you can then sign in on the new phone straight away.
- Or wait until 30 days have passed since the first move.
If you didn't move phones yourself, someone else may be using your account: change your password on the website, turn on two-step sign-in, and remove phones you don't recognise under Phones.