Existing Product Meta: Fatal error after the update

Hello.

I just updated the plugin to version 3.5 today.

And then, not too sure is that related to the plugin, but when I wanted to edit the options, I got the Fatal Error message.

Here is the screenshot: https://i.imgur.com/JldZDV8.jpg

Here is the message:

Fatal error: Uncaught Error: Call to a member function get_product_meta_all() on null in /home/nagoyaex/public_html/wp-content/plugins/woocommerce-product-addon/templates/admin/existing-meta.php:59 Stack trace: #0 /home/nagoyaex/public_html/wp-content/plugins/woocommerce-product-addon/classes/nm-framework.php(498): include_once() #1 /home/nagoyaex/public_html/wp-content/plugins/woocommerce-product-addon/classes/admin.class.php(235): NM_Framwork_V1->load_template(‘admin/existing-…’) #2 /home/nagoyaex/public_html/wp-includes/class-wp-hook.php(298): NM_PersonalizedProduct_Admin->product_meta(”) #3 /home/nagoyaex/public_html/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(”, Array) #4 /home/nagoyaex/public_html/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #5 /home/nagoyaex/public_html/wp-admin/admin.php(222): do_action(‘settings_page_n…’) #6 {main} thrown in /home/nagoyaex/public_html/wp-content/plugins/woocommerce-product-addon/templates/admin/existing-meta.php on line 59

It seems like I cannot edit the options I set before. But those options are still workable on the products, they are still adding optional costs correctly.

Is that because of the update? Or any other conflict you think?

Thank you!

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