ftp_fput fatal error

We are using v2.19.1. The debug.log file is flooded with the below message.

PHP Fatal error: Uncaught TypeError: ftp_fput(): Argument #1 ($ftp) must be of type FTP\Connection, null given in public_html/wp-admin/includes/class-wp-filesystem-ftpext.php:212

Stack trace:

#0 public_html/wp-admin/includes/class-wp-filesystem-ftpext.php(212): ftp_fput()

#1 public_html/wp-content/plugins/ultimate-addons-for-gutenberg/lib/gutenberg-templates/inc/classes/ast-block-templates-notices.php(36): WP_Filesystem_FTPext->put_contents()

#2 public_html/wp-content/plugins/ultimate-addons-for-gutenberg/lib/gutenberg-templates/ast-block-plugin-loader.php(106): Gutenberg_Templates\Inc\Classes\Ast_Block_Templates_Notices->has_file_read_write()

#3 public_html/wp-includes/class-wp-hook.php(324): Gutenberg_Templates\Ast_Block_Plugin_Loader->load_classes()

#4 public_html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters()

#5 public_html/wp-includes/plugin.php(517): WP_Hook->do_action()

#6 public_html/wp-settings.php(726): do_action()

#7 public_html/wp-config.php(114): require_once('/mnt/data/home/...')

#8 public_html/wp-load.php(50): require_once('/mnt/data/home/...')

#9 public_html/wp-admin/admin-ajax.php(22): require_once('/mnt/data/home/...')

#10 {main}

thrown in public_html/wp-admin/includes/class-wp-filesystem-ftpext.php on line 212

It looks like a similar issue here but WP-CLI. https://www.ads-software.com/support/topic/latest-update-causing-cli-fatal-error/

It is not causing to any functionalities we use but it flooded our debug.log file with these messages.

Thanks