code canyon woozone plugin


Hello, I loaded the code canyon woozone plugin on my kingdom theme website. now i cannot login to my wp-admin portal. when i try to login, i receive several error message lines that include the following error message:
Warning: Cannot modify header information - headers already sent by (output started at xxxx/wp-content/plugins/woozone/lib/scripts/debugbar/debugbar.php:343) in xxxx/wp-includes/pluggable.php on line 952

i have deleted cache and cookies. still no luck. please advise. thanks. jean