Howdy Keinan,
Geoff is out for the rest of the week, but I’d be happy to try and pick up where he left off. I might be missing a little backstory here but I’ll do my best to fill in the blanks.
Are the fields setup in WP-Admin > Events > Settings > Additional Fields ? WordPress has its own thing called “custom fields” while ours are called “Additional Fields”. It’s confusingly similar names so I wanted to double check that you are using Additional Fields.
Are all of your plugins up to date and on the same version? Right now Pro, Filter Bar, The Events Calendar and any addons should all be on the 4.1.x versions.
Thanks for reaching out! Please let me know if you have any questions of your own. Cheers!
– Brook