She has been fighting a 3-year battle with the utility over monthly bills that total thousands of dollars.
She has documented this all very well, providing ABC7 with copies of her ComEd bills.
There are plenty of normal bills for a little more than $40, and then the bills suddenly jump to $12,000, $16,000.
It seems comical: an obvious mistake.
So far, ComEd has not fixed it.
Angela Sim says she runs a simple, small cleaning business inside a South Loop condo building. Her space covers about 500 square feet, and other than the iron, lights and a sewing machine, she uses very little electricity.
In fact, for the first four years she was here, her bills used to run a little more than $40 a month. About three years ago, she got a bill from ComEd for much more: Over $10,000 dollars. Naturally, she called ComEd.
After going through several people at ComEd, Sim got the bill fixed for a couple months.
However, she got another huge bill, and another, and another.
One bill was for $27,916. After Sim received that bill, her friend Deb Rowland, an attorney, offered to help.
"I thought, 'OK, I'll get this done in one day,'" said Rowland. "That was three years ago."
In addition to dozens of calls to ComEd, Deb has written letters to Attorney General Lisa Madigan's office and the Illinois Commerce Commission. Still, the problem continues.
"It was corrected for a while, but I don't know what happens down there, but it reset itself again," said Rowland. "We are back to square one."
At one point, Angela says a ComEd employee came out to investigate, looking at a number of meters in the building, which is home to some 300 residences and several businesses, but the huge bills kept coming.
"You have to call customer service and they tap things into their computer, but it's not clear billing actually ever reads it, because if it did this would be resolved," said Rowland.
"It's making me crazy," said Sim. "I am scared for my credit."
A spokesperson for ComEd described the situation as complex and said that they recognize that Sim has been getting incorrect bills for a number of months. They said that ComEd is trying to correct the problem and find out what caused it in the first place.