Good evening Kim and welcome to the Events Calendar Support forum!
Thank you for reaching out to us.
We are sorry to hear about the WooCommerce disappearing on you.
I would love to help you with this topic.
Based on your system information, it looks like the Event Tickets Plus plugin is deactivated for some reason. Reactivating it should restore the functionality.
If that gives you any trouble, delete the plugin (it is safe) and reinstall it from scratch by downloading it from your account.
Let me know how that goes.
Best regards,
Geoff B.