Fatal Error, help needed

I tried to delete a plugin and now receive the follwoing error message:

Fatal error: Cannot redeclare grofiles_attach_cards() (previously declared in /home/content/13/6276313/html/blog/wp-content/plugins/gravatar-hovercard/hovercards.php:16) in /home/content/13/6276313/html/blog/wp-content/plugins/jetpack/modules/gravatar-hovercards.php on line 186

any help is greatly appreciated.