Add new page (ERROR)

I am new and no experience with programming or coding, I will always try and try to find info on the web until it doesn’t work and then ask for help.

I have had major problems with the page after this last update, have decided to leave Woocommerce and have taken Bookly.

Now I am trying to add a new page, after clicking ADD NEW PAGE – I get this error:

Fatal error: Uncaught TypeError: Argument 2 passed to Elementor\TemplateLibrary\Source_Local::on_save_post() must be an instance of WP_Post, null given, called in /home/customer/www/mettaholisticsupport.com/public_html/wp-includes/class-wp-hook.php on line 289 and defined in /home/customer/www/mettaholisticsupport.com/public_html/wp-content/plugins/elementor/includes/template-library/sources/local.php:1086 Stack trace: #0 /home/customer/www/mettaholisticsupport.com/public_html/wp-includes/class-wp-hook.php(289): Elementor\TemplateLibrary\Source_Local->on_save_post(0, NULL) #1 /home/customer/www/mettaholisticsupport.com/public_html/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(0, Array) #2 /home/customer/www/mettaholisticsupport.com/public_html/wp-includes/plugin.php(478): WP_Hook->do_action(Array) #3 /home/customer/www/mettaholisticsupport.com/public_html/wp-includes/post.php(4260): do_action('save_post', 0, NULL, false) #4 /home/customer/www/mettaholisticsupport.com/public_html/wp-admin/includes/post.php(687 in /home/customer/www/mettaholisticsupport.com/public_html/wp-content/plugins/elementor/includes/template-library/sources/local.php on line 1086
There has been a critical error on your website. Please check your site admin email inbox for instructions.

I work with elementor.
Have deactivated it took an other builder, I will not have this error – the page would roll further but there would be a error in the page where I wanted to work in.
The error would be:
Warning: Creating default object from empty value in /home/customer/www/mettaholisticsupport.com/public_html/wp-admin/includes/post.php on line 729

Warning: Cannot modify header information - headers already sent by (output started at /home/customer/www/mettaholisticsupport.com/public_html/wp-admin/includes/post.php:729) in /home/customer/www/mettaholisticsupport.com/public_html/wp-admin/admin-header.php on line 9

Warning: Invalid argument supplied for foreach() in /home/customer/www/mettaholisticsupport.com/public_html/wp-content/plugins/wordpress-seo-premium/admin/metabox/class-metabox.php on line 1034
Once on the page and clicking on the button: ADD BOOKLY – there should be a popup but this doesn’t appear.

Have moved recently from Namecheap to Siteground.
On NC I had constantly 504 error, on SG this…

What is the problem?

• This topic was modified 5 years, 9 months ago by David Stojanovic.
• This topic was modified 5 years, 9 months ago by David Stojanovic. Reason: made block quote
• This topic was modified 5 years, 9 months ago by James Huff.
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The page I need help with: [log in to see the link]