Rescheduling an event is easy if your are the event admin.
Start by clicking on the Event it self then you will be able to Edit the event
Then suggest new suggestion of dates and times if needed.
Then you can confirm the event for the new time.
Pro tip: If the other invitee already knows about the moved event you can confirm it without needing their vote. The event always lands in their calendar after confirmation except they have declined the event 👌