I have found a half solution.
A few months ago, I asked a moderator for advice on making the STATS column appear in excel exports.
He had therefore sent me a new default.php file to replace in the administrator / components / com_contentbuilder / views / export / tmpl folder.
I re-uploaded the original one and no more errors but on the other hand, my STATS column no longer appears in the excel export.
I am attaching the default.php file (with stats column) if someone can possibly fix it for me plz?