No refunds. But here's the good news...
You can repurpose that campaign! Use different phrases for B2C/B2B campaigns. Connect to a different landing page for Web campaigns. Your budget isn't wasted. It's redirected.
Important: If you STOP a campaign (not pause), restarting it will require a new payment. Paused campaigns can be resumed at their current lead balance. When in doubt, pause instead of stop.