undefined array

Hi,

I’ve installed the Groups plugin on a local staging site. I’m getting the following error message:
“Warning: Undefined array key 1 in /Applications/MAMP/htdocs/riders2025/wp-admin/menu-header.php on line 202”

When I go there it’s this:

if ( ! current_user_can( $sub_item[1] ) ) {

Any ideas how to resolve this?

Best, K