Notice: Undefined index: active

Hi, when WP_DEBUG is set to true in wp-config.php I get this notice error on every page:

Notice: Undefined index: active in /var/www/example.com/wp-content/plugins/dp-maintenance-mode-lite/dpMaintenanceLite.php on line 28

Call Stack:
    0.0002     239072   1. {main}() /var/www/example.com/index.php:0
    0.0004     242264   2. require('/var/www/example.com/wp-blog-header.php') /var/www/example.com/index.php:17
    0.0008     256200   3. require_once('/var/www/example.com/wp-load.php') /var/www/example.com/wp-blog-header.php:12
    0.0012     265912   4. require_once('/var/www/example.com/wp-config.php') /var/www/example.com/wp-load.php:29
    0.0025     343216   5. require_once('/var/www/example.com/wp-settings.php') /var/www/example.com/wp-config.php:90
    0.2676   35504440   6. do_action() /var/www/example.com/wp-settings.php:347
    0.4985   39779496   7. call_user_func_array() /var/www/example.com/wp-includes/plugin.php:429
    0.4985   39779528   8. dpMaintenance_initial_run() /var/www/example.com/wp-includes/plugin.php:429

It would be great if you could add the following fix to your plugin to make this notice disappear:

wp-content/plugins/dp-maintenance-mode-lite/dpMaintenanceLite.php
Line: 28 change from:

if($dpMaintenance['active']){ dpMaintenance_activate(); }

To:

if(isset($dpMaintenance['active'])){ dpMaintenance_activate(); }

Thanks in advance

https://www.ads-software.com/plugins/dp-maintenance-mode-lite/