CSRF Protection problem

Hey there,

I have a small problem with csrf protection. I'm using csrf protection for my login site, to login.
Sometimes i get an error:

"An Error Was Encountered
The action you have requested is not allowed."

I'm using the form-helper, to create an proper form.
I have no problems on my localhost, it only happens on the live website.
I have absolutly no idea how I can solve this problem.. could anybody give me suggestions.

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