Allied Interstate's collectors were also badgering Maureen Coffin on behalf of another creditor, Midland Funding, though the suspected debtor was a Lorraine Coffin who lives in another area code. "They were very aggressive and belligerent," Maureen Coffin said. "They told me I was Lorraine Coffin. ... They said, 'You have to be because we have this telephone number and you owe $900."'

"What alarms me," Coffin added, "is that a lot of elderly people may be intimidated by these kinds of calls and say, 'Maybe I forgot, and maybe I should pay."'

Mistaken identity

Cases of mistaken identity, Harmer said, "are a problem, and are an issue for every debt collection agency."

Such mistakes, according to Harmer and other industry officials, involve just a small percentage of cases. But it is a percentage of an enormous number. Allied Interstate, for example, is one of hundreds of debt collection companies pursuing Massachusetts consumers. Yet Allied alone has 396,819 delinquent accounts in Massachusetts, according to Harmer, with 28,244 added just last month. That means Allied has one account for every 16 people in Massachusetts.

Harmer assured the Globe that Allied, by computer link, had alerted the Sherman Financial subsidiary to the Donovan error. But something went awry. Resurgent Capital Services, another Sherman subsidiary, reassigned her case to Frederick J. Hanna & Associates, a Marietta, Ga., debt collection law firm. Last Tuesday, the Hanna firm called her seeking payment of the same bill.

David Alster, the operations manager for the Hanna agency, said during a conference call with Donovan and a Globe reporter last Wednesday that Donovan had been wronged. During the conversation, Alster did a further database search, using the actual debtor's Social Security number, and discovered that her last name is Doyle. He said he was at a loss to explain how the debt buyer could have had the wrong name, address, and telephone number.

In interviews with the Globe, Harmer, Alster, and a spokeswoman for Resurgent all apologized for the treatment of Donovan.

Also inexplicable is how Capital One could have targeted the wrong Eileen Myers — and paid no heed to her protestations that she was being wrongly targeted.