LOS ANGELES (KABC) -- It's been two years since a 39-year-old mother was last seen walking in downtown Los Angeles before she vanished without a trace.
Heidi Planck was last seen alive in October 2021. Her friends and family may have accepted the fact that she is dead, but they're trying to keep her name and face front and center.
There's billboards up across parts of L.A. asking for help in solving the cold case. The billboards are up in places where Planck worked and dined, said a good friend who did not want to be identified.
Earlier this year, Planck was legally declared dead even though her body has never been found.
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She was last seen in downtown L.A., where surveillance video showed her walking near a high-rise known as the Hope + Flower building on Hope Street.
Her dog was later found inside that building. Her SUV was found in a parking garage several blocks away.
Los Angeles police says forensic evidence found in the apartment building leads them to believe an incident happened there. A search for her body began in the Chiquita Canyon Landfill in Castaic about a month after her disappearance.
"LAPD feels confident that there are at least four, five individuals who know exactly what happened to Heidi that day," Planck's friend said. "And I don't care who you are or where you come from, nobody deserves to be thrown out like trash."
Planck's friends and family are hoping to spur someone who knows more about her fate to come forward.
"It's hard. You figure out how to talk about the person in past tense, which I still don't do all the time," the friend said. "But like I said, it's been two years, but it also feels like time has stood still a little bit."