Warning: Constant ABSPATH already defined in /home/public/wp-config.php on line 21

Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, first array member is not a valid class name or object in /home/public/wp-content/plugins/jetpack/class.jetpack-sync.php:65 Stack trace: #0 /home/public/wp-content/plugins/jetpack/modules/notes.php(24): Jetpack_Sync::sync_options('/home/public/wp...', 'home', 'blogname', 'siteurl', 'permalink_struc...', 'category_base', 'tag_base', 'comment_moderat...', 'default_comment...', 'thread_comments', 'thread_comments...') #1 /home/public/wp-content/plugins/jetpack/class.jetpack.php(750): require('/home/public/wp...') #2 /home/public/wp-includes/plugin.php(505): Jetpack::load_modules('') #3 /home/public/wp-settings.php(237): do_action('plugins_loaded') #4 /home/public/wp-config.php(22): require_once('/home/public/wp...') #5 /home/public/wp-load.php(29): require_once('/home/public/wp...') #6 /home/public/wp-blog-header.php(12): require_once('/home/public/wp...') #7 /home/public/index.php(17): require('/home/public/wp...') #8 {main} thrown in /home/public/wp-content/plugins/jetpack/class.jetpack-sync.php on line 65