Collaborators in China cannot sign up for free account?



I recently created a new smartsheet workspace and shared it with collaborators in China. For some reason when they go to set up a new account (free user as our Institute has the license) the page will not jump and allow them to create an account. We have collaborators in Europe and Japan who were able to set up an account without issue.

Has anyone experienced this same issue? Is Smartsheet not accessible in China?

Thank you!!