PHP fatal error on plugin settings page

Hello,

I would like to let you know that there is a PHP warning and a fatal error in this URL:

https://www.domain.com/wp-admin/options-general.php?page=breadcrumb-navxt

Just at the end, with no “save options” button available:

Warning: Undefined array key "Hpost_saswp_reviews_template" in /home/user/domain.com/wp-content/plugins/breadcrumb-navxt/class.bcn_admin.php on line 430

and

Fatal error: Uncaught TypeError: mtekk\adminKit\form::textbox(): Argument #1 ($option) must be of type mtekk\adminKit\setting\setting, null given, called in /home/user/domain.com/wp-content/plugins/breadcrumb-navxt/class.bcn_admin.php on line 430 and defined in /home/user/domain.com/wp-content/plugins/breadcrumb-navxt/includes/adminKit/class-mtekk_adminkit_form.php:179 Stack trace: #0 /home/user/domain.com/wp-content/plugins/breadcrumb-navxt/class.bcn_admin.php(430): mtekk\adminKit\form->textbox() #1 /home/user/domain.com/wp-includes/class-wp-hook.php(303): bcn_admin->admin_page() #2 /home/user/domain.com/wp-includes/class-wp-hook.php(327): WP_Hook->apply_filters() #3 /home/user/domain.com/wp-includes/plugin.php(470): WP_Hook->do_action() #4 /home/user/domain.com/wp-admin/admin.php(259): do_action() #5 /home/user/domain.com/wp-admin/options-general.php(10): require_once('/home/user/...') #6 {main} thrown in /home/user/domain.com/wp-content/plugins/breadcrumb-navxt/includes/adminKit/class-mtekk_adminkit_form.php on line 179

My current setup:
WordPress 5.8.2
Breadcrumb NavXT 7.0
PHP 8 in apache server

In case you need additional information or testing, feel free to let me know. Many thanks for your plugin. 🙏🏻