Eventory Template Error

I purchased the Eventory template late last year. I love the template. It’s very responsive and modern. The only issue I’ve ran into is on my home page. The images are curtain sliders with the title being a hot link. If you click on the link, the following error comes up:

Fatal error: Call to undefined function is_product() in /home/attack8/public_html/wp-content/themes/eventory/extension/theme-scripts.php on line 172

I do not understand this error. Furthermore, I have no idea how to adjust the code from the file manager. I’ve been told that I should update the template, but I’m not sure how to go about doing that unless I have to buy a new template again (which seems ridiculous). I did notice on the live demo that the curtain sliders link to a blog page. I do not have that on my site.

Website: www.attackthedragon.com