Error in WordPress

Site was working, now getting an error page, below are the errors

PHP Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function “_wp_register_default_icon_collections” not found or invalid function name in C:\inetpub\vhosts\rnwritenow.com\httpdocs\wp-includes\class-wp-hook.php:353 Stack trace: #0 C:\inetpub\vhosts\rnwritenow.com\httpdocs\wp-includes\class-wp-hook.php(377): WP_Hook->apply_filters() #1 C:\inetpub\vhosts\rnwritenow.com\httpdocs\wp-includes\plugin.php(522): WP_Hook->do_action() #2 C:\inetpub\vhosts\rnwritenow.com\httpdocs\wp-settings.php(771): do_action() #3 C:\Program Files (x86)\Plesk\Additional\modules\wp-toolkit\wp-cli\vendor\wp-cli\wp-cli\php\WP_CLI\Runner.php(1394): require(‘…’) #4 C:\Program Files (x86)\Plesk\Additional\modules\wp-toolkit\wp-cli\vendor\wp-cli\wp-cli\php\WP_CLI\Runner.php(1313): WP_CLI\Runner->load_wordpress() #5 C:\Program Files (x86)\Plesk\Additional\modules\wp-toolkit\wp-cli\vendor\wp-cli\wp-cli\php\WP_CLI\Bootstrap\LaunchRunner.php(28): WP_CLI\Runner->start() #6 C:\Program Files (x86)\Plesk\Additional\modules\wp-toolkit\wp-cli\vendor\wp-cli\wp-cli\php\bootstrap.php(84): WP_CLI\Bootstrap\LaunchRunner->process() #7 C:\Program Files (x86)\Plesk\Additional\modules\wp-toolkit\wp-cli\vendor\wp-cli\wp-cli\php\wp-cli.php(35): WP_CLI\bootstrap() #8 C:\Program Files (x86)\Plesk\Additional\modules\wp-toolkit\wp-cli\vendor\wp-cli\wp-cli\php\boot-fs.php(17): require_once(‘…’) #9 C:\Program Files (x86)\Plesk\Additional\modules\wp-toolkit\wp-cli\wpt-wp-cli.php(49): require_once(‘…’) #10 {main} thrown in C:\inetpub\vhosts\rnwritenow.com\httpdocs\wp-includes\class-wp-hook.php on line 353 Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function “_wp_register_default_icon_collections” not found or invalid function name in C:\inetpub\vhosts\rnwritenow.com\httpdocs\wp-includes\class-wp-hook.php:353 Stack trace: #0 C:\inetpub\vhosts\rnwritenow.com\httpdocs\wp-includes\class-wp-hook.php(377

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