Can I sue my mortgage holder for harrassing phone calls

I have my mortgage with JP Morgan Chase. I tell them not to call me at work, and they do not listen, every month they call me at work. I have spoken to supervisors on numerous occasions and they say they will take my number out the system. And every month they call me again. This morning, they even left a voice mail at work. How can I stop this. I give them my cell phone, which they never use. I am current with my mortagage, but pay after the due date, but before being 30 days late so it is not reported to the credit agencies. Please note: This is not a third party creditor, they hold the mortgage and my mortgage is current.