There are many reasons your login one-time passcode could be expired. To resolve this issue and make sure you can log in, be sure of the following:
1.) Make sure you are clicking on the most recent email that you have received from Swan, not an old one-time passcode email.
2.) Open the link in a google incognito window. This will ensure that your old cookies or browser plugins are not causing issues with your one-time passcode.
3.) If you're using a VPN, please make sure your VPN is routed through the US.
If none of the above solve the issue please reach out to our support team.