Hi, Dan. Sorry you’re experiencing this.
I’d recommend trying another browser; make sure it doesn’t have privacy-blocking extensions enabled because those can sometimes inadvertently get in the way of such authorizations.
If that doesn’t work, please put your site in temporary troubleshooting mode–basically switching to a default theme and deactivating non-Modern Tribe plugins–and see if you’re then able to authorize.
If still not, keep your site in troubleshooting mode and then enable WP_DEBUG and WP_DEBUG_LOG (which will create a file on your server at /wp-content/debug.log if there are any WP_DEBUG messages) and share any debug messages you see while trying to replicate this issue and doing other things on your site relevant to this ticket (such as visiting your site’s home page, events page, single-event pages, and anything else you can think to do).