BenRon

Same problem here, but I fixed it:

In /includes/class-integrations.php on line 48 and 49 change

$form_id = explode('-', $list_form)[1];
$list_id = explode('-', $list_form)[0];

to

$form_id = explode('-', $list_form[1]);
$list_id = explode('-', $list_form[0]);

and in /includes/class-admin.php change line 333 from

$form_id = explode('-', $list_form)[1];

to

$form_id = explode('-', $list_form[1]);

and line 338 from

$list_id = explode('-', $list_form)[0];

to

$list_id = explode('-', $list_form[0]);