I am having a strange error, but I don't really think its enfold.

Hi Guys,
my hosting company said the error below might be coming from the theme.. but I don’t think so.
have you seen this before? I deactivated all my plugins, and whenever I try to add post or page this happens.
Hope you have an idea.
Thanks
Tina

Notice: Trying to get property ‘post_type’ of non-object in /wordpress/wp-includes/post.php on line 7581 Notice: Trying to get property ‘post_type’ of non-object in /wordpress/wp-includes/post.php on line 7582 Notice: Trying to get property ‘ID’ of non-object in /wordpress/wp-includes/post.php on line 7586 Notice: Trying to get property ‘post_type’ of non-object in /wordpress/wp-includes/post.php on line 7829 Notice: Trying to get property ‘post_type’ of non-object in /wordpress/wp-includes/theme.php on line 3514 Notice: Trying to get property ‘post_type’ of non-object in /wordpress/wp-includes/theme.php on line 3739 Notice: Trying to get property ‘post_type’ of non-object in /wordpress/wp-includes/post.php on line 5361 Notice: Trying to get property ‘ID’ of non-object in /wordpress/wp-includes/post.php on line 5361 Notice: Trying to get property ‘post_type’ of non-object in /wordpress/wp-includes/post.php on line 4662 Fatal error: Uncaught TypeError: Argument 2 passed to aviaPostCssManagement::handler_wp_save_post() must be an instance of WP_Post, null given, called in /wordpress/wp-includes/class-wp-hook.php on line 307 and defined in /www/wp-content/themes/enfold/config-templatebuilder/avia-template-builder/php/class-post-css-management.php:385 Stack trace: #0 /wordpress/wp-includes/class-wp-hook.php(307): aviaPostCssManagement->handler_wp_save_post(0, NULL, false) #1 /wordpress/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters(NULL, Array) #2 /wordpress/wp-includes/plugin.php(476): WP_Hook->do_action(Array) #3 /wordpress/wp-includes/post.php(4673): do_action(‘save_post’, 0, NULL, false) #4 /wordpress/wp-admin/includes/post.php(700): wp_insert_post(Array, false, false) #5 /wordpress/wp-admin/post-new.php(66): get_default_post_to_edit(‘post’, true) #6 {main} thrown in /www/wp-content/themes/enfold/config-templatebuilder/avia-template-builder/php/class-post-css-management.php on line 385
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