As you have a Professional subscription please post to Professional support forums (this is Community Discussions / Languages / French / CB / CB Activités, and your question is not French language translations related).
I would have moved your subject, but as it doesn't have any error message indication, nor indication of Joomla, CB and PHP version, it is easier for you to start a new thread in the Professional support forum here with all those indications:
www.joomlapolis.com/forum/153-professional-member-support
Please also see how to help us help you indications here:
www.joomlapolis.com/help-us-help-you