"I can't stop them," Tanner said after trying several times to contact authorities.
She lost $1,000 to Giblin when he asked to borrow money for a computer while romancing her.
Lamine N'Diayne, spokesman for the agency's Northeast regional office, said Giblin was considered dangerous.
He was in a residential program at the Luzerne Treatment Center in the city's Juniata section, which treats addictions and helps inmates prepare to reenter the community.
Giblin was allowed to leave without supervision Friday to apply for work, but never returned, N'Diayne said. It was the fifth time he had been given a pass.
Giblin has more than 30 convictions, including one for a 1990 sexual assault in Essex County, according to prison officials and court records. Between 2000 and 2005, he had at least 130 paramours, whom he met on chat lines and scammed out of about $330,000.
In 2007, he was given a 15-year sentence by U.S. District Judge Robert B. Kugler, who concluded, "You're a crook, a scam artist."
Giblin sometimes visited his marks and promised to relocate. He asked for hundreds or thousands of dollars to pay for the moves. When a woman refused, he threatened to hurt her children or other relatives.
When Giblin got the funds, he gambled in Atlantic City and Las Vegas. At his sentencing, he apologized and said he needed help.
Another victim, a single mother in North Carolina, said Tuesday that she was notified by the Prison Bureau last summer that Giblin had been transferred to Luzerne. About 2:30 a.m. Saturday, she started receiving a barrage of messages that Giblin was on the loose.
Phone alerts go out automatically to victims who have requested information about an inmate's change in status. In 2007, Giblin's victims were given a code to confirm receipt of the messages, which would halt them. Prison officials could not confirm how many people had received the calls about Giblin, which N'Diayne said were programmed to go out at all hours.
"It's a safety thing," he said.
Those like Tanner who have lost the code to turn off the recordings may call the Prison Bureau at 215-521-7300.
Anyone who comes in contact with Giblin should call local police immediately, authorities said.
Contact Barbara Boyer at 856-779-3838 or firstname.lastname@example.org, or follow on Twitter @BBBoyer.