[Plugin: My Twitter Widget] Fatal Error when inserting 2 widgets of this plugin!

In my blog I would like to show 2 times this plugin’s widget for 2 different twitter feeds.

The first works fine, but when I add a second widget to another footer column, then I get a fatal error (the twitter usernames are definitely right!):

Fatal error: Cannot redeclare jltw_format_since() (previously declared in /home/www/web346/html/sites/wp-content/plugins/my-twitter-widget/my-twitter.php:171) in /home/www/web346/html/sites/wp-content/plugins/my-twitter-widget/my-twitter.php on line 171

How can I use it twice on a blog?

Thanks.

https://www.ads-software.com/extend/plugins/my-twitter-widget/