Zendesk Chat stopped working

This plugin was set up previously and working fine. We recently updated to WordPress 5.+ and it stopped working. When I looked at the page I noticed the Zendesk code was being injected multiple times so I removed the other instances and now it’s only on the page once, inside the head tag where it should be, but the chat widget is still not working and we aren’t getting any errors.

Please advise how to make this work.

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