Critical error on multisite | WordPress.org

Hi, I have been using this plugin well.
A few days ago I converted my single website to network multisite.

And I could see some message like there is critical error on this website from the description section under template name on the setting page of Elementor Header & Footer Builder.

I cannot edit the old templates and the information of shortcode, display rules, date hits is empty on the setting page of Elementor Header & Footer Builder.

Qestion1) Do you have any advice how to solve this?
Qestion2) Is there any way to backup and restore only this plugin contents?

ps) I have a full backup file by updraft, so I think I may extract the essential files you will mention.

Thank you in advance for your reply

 

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