Site: USPSClick-N-Ship: Priority Mail International. Cannot go to checkout page due to this error. This has beed happening for few weeks. Add new comment Comments I've called to try and get help on this but I can't seem to get click-n-ship to work. I need to get my package out ASAP and be able to track it. reply Add new comment Your name * E-mail * The content of this field is kept private and will not be shown publicly. Comment * Notify me when new comments are posted 9cn6Sq Enter the code above * Enter the code without spaces.