Fatal error with class-wp-filesystem-ftpext

Hello. Today I go to the site, which externally works fine, but I can’t go to the admin panel, I can’t do anything in the admin panel, I give such an error.
What does this mean and how to solve it?

Fatal error: Uncaught TypeError: ftp_nlist(): Argument #1 ($ftp) must be of type resource, null given in /sites/vicka.ru/wp-admin/includes/class-wp-filesystem-ftpext.php:438 Stack trace: #0 /sites/vicka.ru/wp-admin/includes/class-wp-filesystem-ftpext.php(438): ftp_nlist(NULL, '/sites/vicka.ru...') #1 /sites/vicka.ru/wp-content/plugins/pagination/bws_menu/bws_functions.php(748): WP_Filesystem_FTPext->exists('/sites/vicka.ru...') #2 /sites/vicka.ru/wp-includes/class-wp-hook.php(310): bws_admin_enqueue_scripts('post-new.php') #3 /sites/vicka.ru/wp-includes/class-wp-hook.php(334): WP_Hook->apply_filters(NULL, Array) #4 /sites/vicka.ru/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #5 /sites/vicka.ru/wp-admin/admin-header.php(118): do_action('admin_enqueue_s...', 'post-new.php') #6 /sites/vicka.ru/wp-admin/edit-form-blocks.php(309): require_once('/sites/vicka.ru...') #7 /sites/vicka.ru/wp-admin/post-new.php(72): require('/sites/vicka.ru...') #8 {main} thrown in /sites/vicka.ru/wp-admin/includes/class-wp-filesystem-ftpext.php on line 438