Form not working

I got this error on the Media – Manage UGC – page
Can you help?

Warning: Cannot modify header information – headers already sent by (output started at …public_html/wp-admin/includes/template.php:1935) in …public_html/wp-content/themes/ifeature/cyberchimps/functions.php on line 1463

The page is
http://kewstudio.org/classes-workshops-tuition/virtual-exhibition/

Many thanks
Sarah

https://wordpress.org/plugins/frontend-uploader/