PHP Error with debug mode enabled

When i search products in the admin search. I receive this error with debug mode active. I disabled all plugins, and activated them one by one, until i detected the error was caused by your plugin.
Also, i left only woocommerce, and woof active and after a couple of searches it started to show the error again.

I don’t see a relation between your plugin and the backend search, but there is something you should check. Thanks!

Notice: Array to string conversion in /home/public_html/domain.com/wp-includes/formatting.php on line 1045

Warning: Cannot modify header information - headers already sent by (output started at /home/public_html/domain.com/wp-includes/formatting.php:1045) in /home/public_html/domain.com/wp-admin/includes/misc.php on line 1114

Warning: Cannot modify header information - headers already sent by (output started at /home/public_html/domain.com/wp-includes/formatting.php:1045) in /home/public_html/domain.com/wp-includes/pluggable.php on line 1216