Fatal error on Pages admin screen

Hi, we are getting the below error on the pages admin screen, which is causing the pages not to appear:

Fatal error: Uncaught TypeError: unserialize(): Argument #1 ($data) must be of type string, array given in /home/sites/13b/9/9534fa8caa/public_html/wp-content/plugins/wp-nested-pages/app/Entities/Listing/ListingRepository.php:39 Stack trace: #0 /home/sites/13b/9/9534fa8caa/public_html/wp-content/plugins/wp-nested-pages/app/Entities/Listing/ListingRepository.php(39): unserialize(Array) #1 /home/sites/13b/9/9534fa8caa/public_html/wp-content/plugins/wp-nested-pages/app/Entities/Listing/Listing.php(317): NestedPages\Entities\Listing\ListingRepository->visiblePages('page') #2 /home/sites/13b/9/9534fa8caa/public_html/wp-content/plugins/wp-nested-pages/app/Entities/Listing/Listing.php(392): NestedPages\Entities\Listing\Listing->listOpening(Array, 0) #3 /home/sites/13b/9/9534fa8caa/public_html/wp-content/plugins/wp-nested-pages/app/Entities/Listing/Listing.php(369): NestedPages\Entities\Listing\Listing->listPostLevel() #4 /home/sites/13b/9/9534fa8caa/public_html/wp-content/plugins/wp-nested-pages/app/Views/listing.php(98): NestedPages\Entities\Listing\Listing->getPosts() #5 /home/sites/13b/9/9534fa8caa/public_html/wp-content/plugins/wp-nested-pages/app/Entities/Listing/Listing.php(280): include('/home/sites/13b...') #6 /home/sites/13b/9/9534fa8caa/public_html/wp-includes/class-wp-hook.php(308): NestedPages\Entities\Listing\Listing->listPosts('') #7 /home/sites/13b/9/9534fa8caa/public_html/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters('', Array) #8 /home/sites/13b/9/9534fa8caa/public_html/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #9 /home/sites/13b/9/9534fa8caa/public_html/wp-admin/admin.php(259): do_action('toplevel_page_n...') #10 {main} thrown in?/home/sites/13b/9/9534fa8caa/public_html/wp-content/plugins/wp-nested-pages/app/Entities/Listing/ListingRepository.php?on line?39

I’ve tried rolling the plugin version back to a few different previous version but that hasn’t helped. Any ideas?

TIA