Customize theme neve in wordpress subsite multisite station

Good morning, I had a high problem complicated, for those who like to overcome problems challenge in wordpress. I have made a multisite station and in a subsite I want to install a new theme different from the main theme. Obviously I have installed it from the administrator and activated it for the site network. Everything is fine until you get to the customization of the theme in question, when I invoke that customization I get this error:
Warning: require_once(/mnt/web218/c2/09/58794009/htdocs/wp-includes/customize/class-wp-customize-background-image-control.php): failed to open stream: No such file or directory in /mnt/web218/c2/09/58794009/htdocs/wp-includes/class-wp-customize-control.php on line 716 Fatal error: require_once(): Failed opening required ‘/mnt/web218/c2/09/58794009/htdocs/wp-includes/customize/class-wp-customize-background-image-control.php’ (include_path=’.:/opt/RZphp72/includes’) in /mnt/web218/c2/09/58794009/htdocs/wp-includes/class-wp-customize-control.php on line 716
I’ve been looking for possible solutions but I can’t find anything, could someone shed some light on this problem? Thank you.

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