Hey there Randyl Errica,
I’m sorry to hear you’ve hit up against difficulties.
The error you cited makes me think that either you are not using the latest version of your plugins or, perhaps more likely, you (or someone working on your behalf) has customized the file referenced in that error message.
Are either of those possible here?
It’s worth highlighting that – except in very unusual situations – editing core plugin files is to be avoided. Instead, you should make any amendments from a template override … this is far safer and there is a great guide to this at the following URL:
theeventscalendar.com/knowledgebase/themers-guide
What I suspect is that you followed a forum post or knowledgebase article describing a way of changing the ticket form and, if so, it may that that guide was out-of-date or perhaps one or two steps were missed when you made the changes.
I hope that helps and let me know if I can provide any more assistance with this 🙂