Hi there,
Thanks for the info. We are not able to log into customer accounts, unfortunately. I have seen this happen before when Jetpack is enabled. Not sure what exactly causes the issue with the conflict, but try deactivated jetpack next time this happens and see if you are able to activate the event tickets plugin.
If that doesn’t help, the next step in troubleshooting this is going to be testing for conflicts with your theme and other plugins (with WP_DEBUG enabled). If you need a testing environment, the free WP Staging plugin will let you create a quick copy of your live site that you can use for testing.
Let me know what you find.
Thanks,
Brendan