Error Thrown

I’ve set up events with Event Calendar and am now trying to get tickets with Event Tickets, which worked for one event, but then when I went to set up a second event with multiple types of tickets, I’m getting this error:

“Error thrown

Call to a member function is_in_stock() on null”

This comes up now on both events when I go to verify that tickets can be purchased through PayPal, even the event that had them working before.

I’ve triple-checked to make sure PayPal is configured to the Tribal Commerce instructions, disabled all other plugins to see if it would work then (it didn’t), and uninstalled Event Calendar and Event Tickets entirely and reinstalled them to see if it would help reset whatever is no longer working (it didn’t). At one point I had gotten WooCommerce’s Event planner as I intend to eventually have WooCommerce up and running for selling products, but had uninstalled it since, and had uninstalled it before uninstalling and reinstalling Event Calendar and Tickets. I know there’s an issue with Event not working with other event management plugins (which I didn’t know before when I got the WooCommerce one to try it out), so now I’m wondering if that screwed things up somehow, but I have no idea how to fix it.

The “Error Thrown” makes me think it’s a php problem, but I’m not confident enough to go in and try and fiddle with the php. I can do that if there’s something I’ve done to a theme that messes up and I can retrieve the original php to reference or copy over, but I can’t quite do that for a plugin.

I’m running Shuttle Blog as my theme, in case that might be relevant info.

Thanks in advance for your help! I’d love to get this fixed ASAP, as we’d like tickets to go up soon.