Howdy Rhonda,
I’m sorry this is giving you such trouble. I would love to help you with this.
I noticed you are running Community Events 4.0.1rc1 on your site. Could you try updating that one first to 4.0.4. Then try upgrading The Events Calendar?
If you continue to see an issue, could you try temporarily disabling all of your other plugins then updating The Events Calendar. I’m guessing it should should update fine. Then try reenabling the other plugins one at a time. Eventually the error will likely crop up again. Which plugin did you enable that caused the error to crop up?
Cheers!
– Brook