Program error output

Hi,
every time i run cron, casch memory cleanup wp-rocket i get these errors, what can i do to fix it?
I would really appreciate your help.

RedisException: Connection refused in /home/host/ftp/mysite.com/wp-content/object-cache.php:636
Stack trace:
#0 /home/host/ftp/mysite.com/wp-content/object-cache.php(636): Redis->connect('127.0.0.1', 6379, 5, NULL, NULL, 5)
#1 /home/host/ftp/mysite.com/wp-content/object-cache.php(485): WP_Object_Cache->connect_using_phpredis(Array)
#2 /home/host/ftp/mysite.com/wp-content/object-cache.php(178): WP_Object_Cache->__construct(true)
#3 /home/host/ftp/mysite.com/wp-includes/load.php(726): wp_cache_init()
#4 /home/host/ftp/mysite.com/wp-settings.php(131): wp_start_object_cache()
#5 /home/host/ftp/mysite.com/wp-config.php(85): require_once('/home/host/...')
#6 /home/host/ftp/mysite.com/wp-load.php(50): require_once('/home/host/...')
#7 /home/host/ftp/mysite.com/rocket-clean-gl.php(4): require('/home/host/...')
#8 {main}