Warning and notice after install

Hello.

I just installed the plugin and i have warning and notice messages in all pages :

• Warning: Missing argument 2 for Awesome_Support_Old::change_plugin_locale() in awesome-support/includes/class-awesome-support.php on line 650
• Notice: Undefined variable: domain in awesome-support/includes/class-awesome-support.php on line 652
• Warning: Cannot modify header information – headers already sent by (output started at awesome-support/includes/class-awesome-support.php:650) in wp-includes/pluggable.php on line 1228

The last warning block redirect send by Polylang plugin, my site is unusable…

Other question, why use a “_Old” in your class name ?

Thanks in advance.

https://wordpress.org/plugins/awesome-support/