Array error on my website

Dear all,

I have a problem with an error that is causing me troubles for a while now. The error I encounter on all the pages where I have a form made with Easy Forms for MailChimp by Yikes is below:

Warning: in_array() expects parameter 2 to be array, string given in /home1/steli86/public_html/wp-content/plugins/yikes-inc-easy-mailchimp-extender/public/classes/checkbox-integrations.php on line 121

I went there to see how it is, but I have no clue on what to write down there so that the error will be rectified. The code I have there on line 121 is the following:

$has_list_ids = $has_list_ids && ! in_array( ‘-‘,

Please help and tell me if there’s any solution for this. Thank you!