Hello zanda18
https://yadi.sk/i/gFvP3Prd3N6a2u
There have mistakes from another plugin (email-before-download) ,
Notice: <code>id</code> property of a <code>WPCF7_ContactForm</code> object is <strong>no longer accessible</strong>. Use <code>id()</code> method instead. in /www/wp-content/plugins/contact-form-7/includes/contact-form.php on line 160
Notice: Undefined index: ebd_downloads in /www/wp-content/plugins/email-before-download/email-before-download.php on line 432
and you use deprecated functions https://contactform7.com/2017/06/07/on-sent-ok-is-deprecated/
And maybe your WordPress working with debug mode .
Check wp-config.php on define('WP_DEBUG', true);
IF there parameter equals true
change it on false