Error after editing the list

Hello!

I get the error when i try to edit the list on the front (not in the admin dashboard).

Warning: trim() expects parameter 1 to be string, array given in hereistheputh/wp-includes/taxonomy.php on line 2443

Warning: Cannot modify header information - headers already sent by (output started at hereistheputh/wp-includes/taxonomy.php:2443) in hereistheputh/wp-includes/pluggable.php on line 1251

Warning: Cannot modify header information - headers already sent by (output started at hereistheputh/wp-includes/taxonomy.php:2443) in hereistheputh/wp-includes/pluggable.php on line 1254

Case:

1. Go to the site, open the Posterno dashboard page.
2. Find the existing list, click Edit.
3. Change something (or not) and save.

I tried to:
– reinstall Posterno
– change theme
– edit other list

Is there any bug? Or it’s a bug on my side? Can’t realize what that is. ??