We're getting the following error:
"You are not authorized to perform this action - Reason: Secure Forms Timeout"

Every time we submit step 1 of a multi-page form. It was working fine yesterday.
We get the same error if we try to go back from step 2 to step 1, for example.

I'm attaching the form template in an html file.

Can you please help? The form is published and it should be heavily used on a trade show during this weekend! Thanks in advance!