Getting Error Mesage

After I try to add a form element, I get this message:

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Error Occured. We are sorry for the inconvenience.

Please try again after some time or refresh the page and try again.

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I have about 8 form elements already but now I can't add any more because I get that message after I click "Done" in the form element edit window.

I have refreshed and waited for a while, but I still get this message.