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Your LimeSurvey version:  LimeSurvey Cloud   Version 6.3.0
Own server or LimeSurvey hosting: LimeSurvey hosting
Survey theme/template: extends_fruity
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Since a few days I can't make any copy of my survey. I get this error everytimes I try :500: Internal Server Error XMLWriter::writeElement(): Argument #2 ($content) must be of type ?string, stdClass givenAn internal error occurred while the Web server was processing your request.
Please contact Your Name to report this problem.

Thank you.
 

You are paying for cloud hosting so you can contact LimeSurvey support directly.

Will do. Thank you.