Error mysqli_query in wp-dp

Hello,

Since some days without any update, I have this error message on my website :
Warning: mysqli_query(): Error reading result set’s header in /home/clients/eabc66cbb4209afa7a73b3e19a8e5ec3/web/wp-includes/wp-db.php on line 1925
Warning: mysqli_query(): MySQL server has gone away in /home/clients/eabc66cbb4209afa7a73b3e19a8e5ec3/web/wp-includes/wp-db.php on line 1925
Warning: mysqli_query(): Error reading result set’s header in /home/clients/eabc66cbb4209afa7a73b3e19a8e5ec3/web/wp-includes/wp-db.php on line 1925

The line 1925 in wp-dp is this :
$this->result = mysqli_query( $this->dbh, $query );

I have already repeat the database and put a new wp-dp files. But always the same error message.

Did somebody have an idea to repair this ?

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