You have full of disk space on hosting. You should write to hoster

during installation by this error

Installing Plugin: Visual Composer

Scompattamento del pacchetto…

Installazione plugin…

Warning: copy(/home/mhd-01/www.eweki.it/htdocs/wp-content/plugins/js_composer/locale/js_composer-de_DE.mo): failed to open stream: Disk quota exceeded in /home/mhd-01/www.eweki.it/htdocs/wp-admin/includes/class-wp-filesystem-direct.php on line 243

Warning: copy(/home/mhd-01/www.eweki.it/htdocs/wp-content/plugins/js_composer/locale/js_composer-de_DE.mo): failed to open stream: Disk quota exceeded in /home/mhd-01/www.eweki.it/htdocs/wp-admin/includes/class-wp-filesystem-direct.php on line 243

Impossibile copiare il file. /home/mhd-01/www.eweki.it/htdocs/wp-content/plugins/js_composer/locale/js_composer-de_DE.mo

Installazione del plugin fallita.

how can I solve it ?