MCI is a bad company, you should just never use them. Besides securities fraud and conspiracy, as claimed by our government against this ugly company when they were MCI WorldCom... they are a customer service nightmare.
For a FULL 2 YEARS after I cancelled long distance service with this joke of a company, they sent me bills!! Every few months I would call them & they would credit me, say they would fix it, & THEY WOULD CONTINUE TO SEND ME BILLS. Even after I cancelled service completely ( I still had them for local service for awhile ), they sent me bills & collection letters. After finally asking a sympathetic collections person (can you believe it a "sympathetic collections person"? see how bad mci is!?!) what sort of legal recourse I had against this harassing company, the bills finally stopped. This is service at its worth & probably criminal. Customer Service lines always took at least 30 minutes to speak to someone. I always felt sorry that these people had to work for such crap.
Switch to Working Assets. Working Assets the best customer service I've experienced in a telephone company. MCI JUST SUCKS.