MCM Midland Credit Managment Company Major Harrassment-Violate Call Laws San Diego California

 MCM calls me a minimum of 5 times a day to collect a debt on behalf of verizon.  I have NEVER had verizon and it apparently is for an old alltel account.  The claim I never turned my phone in which I did ship back but since it was over 3 years ago I do not have the information for and they are going to charge me almost $400.00 for this.  They have been harassing me for over 3 years and even offered to cut my payment in half if I would pay.  I refuse to pay on something that I do not owe, and HOW DO THEY KNOW IF I SHIPPED MY PHONE back or not?  Alltel is no longer!! I told them to take me to court or leave me alone, can they actually affect my credit score?  I have spent hours on the phone/letters/faxes and highblood pressure over this issue on and off for the past three years and would like to end it! 

By the way everyday the calls begin at 6:30am and last until about 10:00pm at night.  A minimum of 5 calls a day.  I want to change my number but I have had it so long and am in sales that it would do more damage than help me.