Please help me to solve these messages:
Warning: Attempt to read property “post_content” on null in /var/www/clients/client1/web2/web/wp-content/plugins/js_composer/include/classes/core/class-vc-base.php on line 331
Deprecated: preg_match(): Passing null to parameter #2 ($subject) of type string is deprecated in /var/www/clients/client1/web2/web/wp-content/plugins/js_composer/include/classes/core/class-vc-base.php on line 357
Deprecated: preg_match_all(): Passing null to parameter #2 ($subject) of type string is deprecated in /var/www/clients/client1/web2/web/wp-content/plugins/js_composer/include/classes/core/class-vc-base.php on line 361
Warning: Attempt to read property “post_content” on null in /var/www/clients/client1/web2/web/wp-content/plugins/js_composer/include/classes/core/class-vc-base.php on line 331
Deprecated: preg_match(): Passing null to parameter #2 ($subject) of type string is deprecated in /var/www/clients/client1/web2/web/wp-content/plugins/js_composer/include/classes/core/class-vc-base.php on line 357