Error: [] operator not supported for strings

When upgrading to latest version 3.5.4 with Word press version 5.0.3 we get this errors and as you can see at the page the first page is blank. The error below is at line 1746 but we also get it at line 1734. They looks like this:

					$metaquery []= 
						        array(
						            
						            'key' => '_auction_closed',
						            'compare'=> 'NOT EXISTS'				        
						    );

and 

							$taxquery []= 
						        array(
						            'taxonomy' => 'product_type',
						            'field' => 'slug',
						            'terms' => 'auction',
						            'operator'=> 'NOT IN'				        
						    );
 
What do you suggest?

I am not familiar with the site so it might be that somebody has made changes to the file locally at the site.

2019-02-07T06:58:57+00:00 CRITICAL Uncaught Error: [] operator not supported for strings in /home/dtstamps/public_html/wp-content/plugins/woocommerce-simple-auctions/woocommerce-simple-auctions.php:1746
Stack trace:
#0 /home/dtstamps/public_html/wp-content/plugins/woocommerce-simple-auctions/woocommerce-simple-auctions.php(1766): WooCommerce_simple_auction->pre_get_posts(Object(WP_Query))
#1 /home/dtstamps/public_html/wp-includes/class-wp-hook.php(286): WooCommerce_simple_auction->auction_arhive_pre_get_posts(Object(WP_Query))
#2 /home/dtstamps/public_html/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(NULL, Array)
#3 /home/dtstamps/public_html/wp-includes/plugin.php(515): WP_Hook->do_action(Array)
#4 /home/dtstamps/public_html/wp-includes/class-wp-query.php(1634): do_action_ref_array('pre_get_posts', Array)
#5 /home/dtstamps/public_html/wp-includes/class-wp-query.php(3230): WP_Query->get_posts()
#6 /home/dtstamps/public_html/wp-includes/class-wp-query.php(3336): WP_Query->query(Array)
#7 /home/dtstamps/public_html/wp-content/theme in /home/dtstamps/public_html/wp-content/plugins/woocommerce-simple-auctions/woocommerce-simple-auctions.php on line 1746

• This topic was modified 7 years, 3 months ago by Jan Dembowski.
• This topic was modified 7 years, 3 months ago by Jan Dembowski.

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