Mautic Installation Wizard

I installed the MAUTIC crm on my siste but I get tihis erron when I lauch the Mautic Installation Wizard.
I get this error:
Fatal error: require(): Failed opening required '/home/customer/www/mautic.attestazionecapacitafinanziariaautotrasportatori.info/public_html/vendor/composer/../symfony/polyfill-mbstring/bootstrap.php' (include_path='.:/usr/local/php74/pear') in /home/customer/www/mautic.attestazionecapacitafinanziariaautotrasportatori.info/public_html/vendor/composer/autoload_real.php on line 71