SP2013 / INFOPATH : The security validation for this form is invalid, Canary data has been tampered with

Hello,

Some US user have the following error when InfoPath display form into SharePoint "The security
validation for this form is invalid, Canary data has been tampered with"

The same InfoPath form was correctly display  for europeen User.

how it is possible to have two distinct behavior?

We using F5 and claims/ADFS , US user has try to clear IE cache without result..

Thanks for your help.