Using shortcode multiple times = fatal error

WP-Piwik 0.9.9.12

Put two shortcodes on a page, you will get:

Cannot redeclare summize() (previously declared in /var/www/html/site.com/wp-content/plugins/wp-piwik/shortcodes/overview.php:13) in /var/www/html/site.com/wp-content/plugins/wp-piwik/shortcodes/overview.php on line 13

https://ww.wp.xz.cn/plugins/wp-piwik/