Log into VAN, and click through until you are in the right committee in My Campaign.
Search for Event List if it's not already displayed in your menu bar. Click into Event List.
Using the Filters, search for the events you need to delete from VAN. Each Mobilize event timeslot syncs as its own event in VAN, even if it's technically the same event on Mobilize.
Click on the event's name to see its settings.
Click Delete Event.
Do this for all instances of Mobilize event(s) that need to be deleted so we can re-sync for you!