Constant Contact Events Not Showing

I am unable get my constant contact events to appear on my website. When I go to the Events section of the Constant Contact plugin, the following message appears.

Warning: Invalid argument supplied for foreach() in /home3/jratliff/public_html/wp-content/plugins/constant-contact-api/admin/events.php on line 523

I can press the Refresh Events button and the events pull in from the CC website – but then they disappear as soon as you leave the page.

https://www.ads-software.com/plugins/constant-contact-api/