I've received the same call twice a week for the past six months - they leave a canned message on my machine.   Pleasant female voice....    "Congratulations.  On your excellent payment history you now qualify for zero percent interest rates on all your credit card accounts.  If you have completed this process or not interested, press 3 now.  Otherwise press 1 now to speak to our qualification department and complete the process.  The qualification process can be completed in a few minutes."

Each time they call - it's from a different number, so saving the number in my blocked list doesn't work...