[Support needed] My pages are blank, cant be modified

Hello to the community. I hope this is the right location to ask for this

I recently bought the Total theme to build my own small website, nothing big (www aurelien hyphen bleriot dot fr)
However, since yesterday, all the default pages i haven’t used and the new page i create are blank and i can’t modify them in any way (Visual Composer for instance) (ex : click on “Expériences SEO”)

Are you familiar with such a problem that is probably easy to overcome ? Is this simply a matter of a box to tick/untick ?

Best regards

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