My draft has started is there any way to stop the draft and reschedule ?
There's no way to stop a live draft once it starts and the applet counts down and there is a user in the draft room. You'd have to wait for it to finish and then reschedule a live draft.
Is there an easy way to schedule a redraft?
Yes, just head to League>>Settings>Edit Live Draft Options and you can schedule it to start within a 30 minute period.