Legal help

I need a cease and desist I think. I own a pet waste removal business here in Las Vegas and I use independent contractors to service my clients. I recently found one of them working for a competitor while working for me. I then sent out non disclosure and no competes for everyone to sign and this one refused. I stopped giving her jobs less than a week ago and so far, I've lost 10 of her assigned clients when she worked for me. Only her clients, none of my other technicians. She received client lists with contact information daily to get her routes. She he has taken advantage of those schedules and info in her emails to take clients to her current pet waste removal company. I'd like to demand that those emails and info be destroyed. I'm really not sure what else to do. So far, those clients that have cancelled with no reason since then, account for almost $12k in annual revenue. Please help. Timeline is ASAP.