Uncaught TypeError: Cannot read property ‘dispatchEvent when submitting

When I try submitting the form, I get the following error:

Please find below:

Uncaught TypeError: Cannot read property ‘dispatchEvent’ of undefined
at Object.wpcf7.triggerEvent (scripts.js?ver=5.0.1:370)
at ajaxSuccess (scripts.js?ver=5.0.1:288)
at Object.<anonymous> (scripts.js?ver=5.0.1:353)
at i (jquery.js?ver=1.12.4:2)
at Object.fireWith [as resolveWith] (jquery.js?ver=1.12.4:2)
at y (jquery.js?ver=1.12.4:4)
at XMLHttpRequest.c (jquery.js?ver=1.12.4:4)

I’d appreciate any input on what the issue might be.

The page I need help with: [log in to see the link]