Help with null error / slow load

Hello – I am getting this error along with very slow load times on my NextGen galleries, can you help? Thanks!

“

ERROR Attempt to read property “ID” on null-

1. wp-includes/link-template.php:394
2. get_page_link()
   wp-content/plugins/nextgen-gallery/src/DisplayTypes/Albums/SharedController.php:895
3. Imagely\N\D\A\SharedController->prepare_display_settings()
   wp-content/plugins/nextgen-gallery/src/DisplayTypes/Albums/SharedController.php:229
4. Imagely\N\D\A\SharedController->enqueue_frontend_resources()
   wp-content/plugins/nextgen-gallery/src/Display/DisplayManager.php:150
5. Imagely\N\D\DisplayManager::enqueue_frontend_resources_for_displayed_gallery()
   wp-content/plugins/nextgen-gallery/src/Display/DisplayManager.php:112
6. Imagely\N\D\DisplayManager::enqueue_frontend_resources_for_content()
   wp-content/plugins/nextgen-gallery/src/Display/DisplayManager.php:53
7. Imagely\N\D\DisplayManager->enqueue_frontend_resources()
   wp-includes/class-wp-hook.php:324
8. do_action('wp_enqueue_scripts')
   wp-includes/script-loader.php:2262
9. wp_enqueue_scripts()
   wp-includes/class-wp-hook.php:324
10. do_action('wp_head')
    wp-includes/general-template.php:3052
11. wp_head()
    wp-content/themes/boldgrid-pavilion/templates/head.php:16
12. load_template('wp-content/themes/boldgrid-pavilion/templates/head.php')
    wp-includes/template.php:725
13. locate_template()
    wp-includes/general-template.php:206
14. get_template_part('templates/head')
    wp-content/themes/boldgrid-pavilion/base.php:32

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