Indefined variable value, title, placeholder

Hi,
I just installed the plugin and add the shortcode in my template.

I got an error on the generated input:
<br />
<b>Notice</b>: Undefined variable: value in <b>/var/www/interstices/web/wp-content/plugins/wp-autosearch/helper/helper.php</b> on line <b>209</b><br />

I also got the same error for values placeholder, title etc…

I checked the file helper.php and in fact the varaibles are not defined before, is it normal ?

How can I fix it ?

Thank you in advance.
Romain Darbas