can not install the social theme

Fatal error: Cannot redeclare bp_dtheme_ajax_querystring() (previously declared in /home6/internf7/public_html/wp/wp-content/plugins/buddypress/bp-themes/bp-default/_inc/ajax.php:20) in /home6/internf7/public_html/wp/wp-content/themes/bp-social/_inc/ajax.php on line 63

solution here
https://premium.wpmudev.org/forums/topic/fatal-error-after-social-theme-activation