Fatal error: Uncaught TypeError: ftp_mkdir(): Argument #1 ($ftp) must be of type FTP\Connection, null given in /var/www/html/wp-admin/includes/class-wp-filesystem-ftpext.php:580
Stack trace:
#0 /var/www/html/wp-admin/includes/class-wp-filesystem-ftpext.php(580): ftp_mkdir(NULL, '/var/www/html/w...')
#1 /var/www/html/wp-content/plugins/seo-by-rank-math/includes/modules/sitemap/class-cache.php(79): WP_Filesystem_FTPext->mkdir('/var/www/html/w...', 493)
#2 /var/www/html/wp-content/plugins/seo-by-rank-math/includes/modules/sitemap/class-cache.php(52): RankMath\Sitemap\Cache->is_writable()
#3 /var/www/html/wp-content/plugins/seo-by-rank-math/includes/modules/sitemap/class-sitemap-xml.php(80): RankMath\Sitemap\Cache->__construct()
#4 /var/www/html/wp-content/plugins/seo-by-rank-math/includes/modules/sitemap/class-router.php(79): RankMath\Sitemap\Sitemap_XML->__construct('1')
#5 /var/www/html/wp-includes/class-wp-hook.php(324): RankMath\Sitemap\Router->request_sitemap(Object(WP_Query))
#6 /var/www/html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters('', Array)
#7 /var/www/html/wp-includes/plugin.php(565): WP_Hook->do_action(Array)
#8 /var/www/html/wp-includes/class-wp-query.php(1154): do_action_ref_array('parse_query', Array)
#9 /var/www/html/wp-includes/class-wp-query.php(1897): WP_Query->parse_query()
#10 /var/www/html/wp-includes/class-wp-query.php(3949): WP_Query->get_posts()
#11 /var/www/html/wp-includes/class-wp.php(701): WP_Query->query(Array)
#12 /var/www/html/wp-includes/class-wp.php(821): WP->query_posts()
#13 /var/www/html/wp-includes/functions.php(1342): WP->main('')
#14 /var/www/html/wp-blog-header.php(16): wp()
#15 /var/www/html/index.php(17): require('/var/www/html/w...')
#16 {main}
  thrown in /var/www/html/wp-admin/includes/class-wp-filesystem-ftpext.php on line 580

Fatal error: Uncaught TypeError: ftp_nlist(): Argument #1 ($ftp) must be of type FTP\Connection, null given in /var/www/html/wp-admin/includes/class-wp-filesystem-ftpext.php:438
Stack trace:
#0 /var/www/html/wp-admin/includes/class-wp-filesystem-ftpext.php(438): ftp_nlist(NULL, '/var/www/html/w...')
#1 /var/www/html/wp-admin/includes/class-wp-filesystem-ftpext.php(456): WP_Filesystem_FTPext->exists('/var/www/html/w...')
#2 /var/www/html/wp-content/plugins/woocommerce/src/Internal/Admin/Logging/FileV2/File.php(254): WP_Filesystem_FTPext->is_file('/var/www/html/w...')
#3 /var/www/html/wp-content/plugins/woocommerce/src/Internal/Admin/Logging/FileV2/File.php(437): Automattic\WooCommerce\Internal\Admin\Logging\FileV2\File->is_writable()
#4 /var/www/html/wp-content/plugins/woocommerce/src/Internal/Admin/Logging/FileV2/FileController.php(135): Automattic\WooCommerce\Internal\Admin\Logging\FileV2\File->write('2025-09-21T21:3...')
#5 /var/www/html/wp-content/plugins/woocommerce/src/Internal/Admin/Logging/LogHandlerFileV2.php(62): Automattic\WooCommerce\Internal\Admin\Logging\FileV2\FileController->write_to_file('fatal-errors', '2025-09-21T21:3...', 1758490329)
#6 /var/www/html/wp-content/plugins/woocommerce/includes/class-wc-logger.php(189): Automattic\WooCommerce\Internal\Admin\Logging\LogHandlerFileV2->handle(1758490329, 'critical', 'Uncaught TypeEr...', Array)
#7 /var/www/html/wp-content/plugins/woocommerce/includes/class-wc-logger.php(236): WC_Logger->log('critical', 'Uncaught TypeEr...', Array)
#8 /var/www/html/wp-content/plugins/woocommerce/includes/class-woocommerce.php(438): WC_Logger->critical('Uncaught TypeEr...', Array)
#9 [internal function]: WooCommerce->log_errors()
#10 {main}
  thrown in /var/www/html/wp-admin/includes/class-wp-filesystem-ftpext.php on line 438