Autoload error

Module 'Magepow_Sitemapexclusion' from '/var/www/sarpsborgmetall-no.live.convert.no/www/app/code/Magepow/Sitemapexclusion' has been already defined in '/var/www/sarpsborgmetall-no.live.convert.no/www/vendor/magepow/sitemapexclusion'.