Fatal error with plugin

This worked fine at first, but now it doesn’t – not sure what happened.

It doesn’t display on the front end, but I have the shortcode in a Divi editor code block on the page. It shows up on the Divi editor as it should – just not on the front end.

When I go to edit page settings in the WP admin panel, I get this error:

Fatal error: Uncaught Error: Call to a member function get() on null
in /home/ia/www/vocationministry.com/wp-content/plugins/wpc-order-tip/includes/class-frontend.php on line 108

Call stack:

1. Wpcot_Frontend::get_tips()
   wp-content/plugins/wpc-order-tip/includes/class-frontend.php:92
2. Wpcot_Frontend::shortcode()
   wp-includes/shortcodes.php:434
3. do_shortcode_tag()
4. preg_replace_callback()
   wp-includes/shortcodes.php:273
5. do_shortcode()
   wp-includes/class-wp-hook.php:324
6. WP_Hook::apply_filters()
   wp-includes/plugin.php:205
7. apply_filters()
   wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php:1933
8. WP_REST_Posts_Controller::prepare_item_for_response()
   wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php:635
9. WP_REST_Posts_Controller::get_item()
   wp-includes/rest-api/class-wp-rest-server.php:1292
10. WP_REST_Server::respond_to_request()
    wp-includes/rest-api/class-wp-rest-server.php:1125
11. WP_REST_Server::dispatch()
    wp-includes/rest-api.php:576
12. rest_do_request()
    wp-includes/rest-api.php:2957
13. rest_preload_api_request()
14. array_reduce()
    wp-includes/block-editor.php:753
15. block_editor_rest_api_preload()
    wp-admin/edit-form-blocks.php:77
16. require('/home/ia/www/vocatio...edit-form-blocks.php')
    wp-admin/post.php:187

Disabling the plugin makes the error go away, of course!

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