Often corporate or private email systems block or delay emails from certain senders to prevent spam and unwanted messages. This can affect emails from Centtrip containing login authentication codes.
Corporate accounts
To fix this issue, your IT/technical team will need to create a 'permitted sender policy' by creating a rule:
for emails from noreply@centtrip.com and/or
for emails with the return address (mail envelope from) "@track.centtrip.com".
More information about permitted sender policies is available here: Mimecaster Central.
Personal accounts
If the email address you use to login to Centtrip is not managed by a corporate admin, adding noreply@centtrip.com to your safe senders email list should mean these emails arrive before the code expires.