Hey!
Thanks for reaching out to the forums.
Based on the description of your issue it seems like the events are being stored in cache still, this usually is done using a feature from WordPress called transients. You can delete all the transients by using a plugin called Transients Manager. After that you can go to:
Tools > Transients
And then click on the button Delete Transients with an Expiration and Delete Expired Transients. After that make sure to remove the cache from any other Cached plugin that you might have installed and take another look.
Please let me know if you have any other questions about this issue or if there’s anything else I can do for you.
Thanks,
Crisoforo