Hi,
Sorry for the issues you are having.
I can help out here.
The Facebook Events plugin is an importer only and does a sync. It cannot detect changes in Facebook.
So if you make changes or delete in Event in Facebook you have to do the same in your WordPress Install.
If you believe the plugin was suppose to do this can you please let us know what lead you to believe that so we can fix it on our site.
Timezone
What is your timezone set in WordPress?
Admin > Settings > General > “Timezone”
Is that set to your local time?
Let me know and we can go from here.
Thanks