Hi Richard,
Thanks for taking the time to reach out to us here! While we’re not equipped to provide technical support for current plugin users here in our pre-sales forum, our technical team would be more than happy to assist you on our WordPress.org support forum for The Events Calendar. Would you mind taking a moment to open a new thread over there?
https://wordpress.org/support/plugin/the-events-calendar
If you can, please take the time to confirm in your post that you’ve run through our conflict testing steps prior to contacting us–this will save us a step and help us to get your issue resolved that much quicker. Since your issue appears to be related to a third-party theme, a link to your site would also be hugely helpful!
Thanks again, and we’ll see you in the forums!