Admin screen not working wordpress compatibility bug

Hi we are getting the following error in our chat plugin. The admin screen from the wordpress dashboard wont load at all.

Note I have replaced the domain name with DOMAINNAME to protect the site.

AH01071: Got error 'PHP message: PHP Warning: Undefined property: Jivosite::$widget_id in /var/www/vhosts/DOMANNAME.co.uk/httpdocs/wp-content/plugins/jivochat/class-jivosite.php on line 256PHP message: PHP Fatal error: Uncaught Error: Cannot use object of type WP_Error as array in /var/www/vhosts/DOMANNAME.co.uk/httpdocs/wp-content/plugins/jivochat/class-jivosite.php:373\nStack trace:\n#0 /var/www/vhosts/DOMANNAME.co.uk/httpdocs/wp-content/plugins/jivochat/class-jivosite.php(352): Jivosite->fetch_supported_languages()\n#1 /var/www/vhosts/DOMANNAME.co.uk/httpdocs/wp-content/plugins/jivochat/class-jivosite.php(257): Jivosite->get_language_list()\n#2 /var/www/vhosts/DOMANNAME.co.uk/httpdocs/wp-content/plugins/jivochat/class-jivosite.php(101): Jivosite->render()\n#3 /var/www/vhosts/DOMANNAME.co.uk/httpdocs/wp-includes/class-wp-hook.php(324): jivosite_preferences()\n#4 /var/www/vhosts/DOMANNAME.co.uk/httpdocs/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters()\n#5 /var/www/vhosts/DOMANNAME.co.uk/httpdocs/wp-includes/plugin.php(517): WP_Hook->do_action()\n#6 /var/www/vhosts/DOMANNAME.co.uk/httpdocs/wp-admin/admin.php(259): do_action()\n#7 {main}\n thrown in /var/www/vhosts/hireka…', referer: https://www.DOMANNAME.co.uk/wp-admin/

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