Hi Doug,
I can’t help since we don’t see any code.
What you can do is:
- Post your page code
- tell us wat line gives the error. (Its normally displayed next to the error line)
- check for updates from wix.
And see if there is anything you use that has been updated.
Als, you tell us you get the error in preview.
Does it also displays in the console on the live website?
If we can’t figure it out you can contact wix support, or if you aren’t afraid me looking at your code, you could make a copy of your website and invite me as a contributor so i can take a look.
NOTE: I’m not velo expert, or in any way connected to the wix team, i’m just someone that likes to help where i can 
Kind regards,
Kristof