LOS ANGELES (NewsNation Now) — The only sign of Heidi Planck since last month was when her dog turned up in a high rise apartment building in downtown Los Angeles.

Planck doesn’t live there.

The 39-year-old, divorced mother has not been seen since Oct. 17, when she was caught on video leaving her home.

“[It’s] absolutely abnormal,” said Danielle Nadolny, Planck’s best friend. “She would never ever ever just leave.”

On that October morning, Planck drove off in her Range Rover with her dog to meet her ex-husband at their son’s football game. But Planck left suddenly at halftime and hasn’t been seen since.

“She didn’t seem agitated, Planck’s ex-husband, Jim Wayne, told NewsNation affiliate KTLA. “She might’ve been a little bit antsy, but she left with her dog and she just walked up to us and said, ‘I’m gonna go.’”

Hours later, the dog was found wandering on the 29th floor of a luxury high rise downtown, but there was no sign of her. Loved ones say Planck has no known ties to the building.

Her friends say she’s too devoted to her son to vanish on purpose.

“She would never do this to her boy,” Natalie John said. “She has worked so hard in her custody battle for this little boy. I’m his godmother and I’ve seen this from the beginning to the end.”

Investigators are considering whether Planck’s disappearance is somehow linked to her job as a financial controller at Camden Capital Partners. Her employer is under federal investigation in an alleged $43 million fraud scheme.

“She didn’t go into much detail,” John said. “She was just very stressed and nervous.”

Federal agents and Los Angeles Police Department officials served a warrant at Planck’s home last week, apparently seeking evidence linked to the fraud investigation. 

“I just know that we’re still missing Heidi and we don’t have her back and I’ve got a 10-year-old boy that’s just beside himself,” Wayne told KTLA.

“This is not her,” John said. “It’s so unlike her and so bizarre and we just want her to know — hopefully she’s listening — we want her home. We’re going to give her a big hug.”

Planck’s son is set to mark his eleventh birthday this week. Her friends said she was looking forward to spending Thanksgiving back home in Buffalo, New York, and going to an upcoming LA Rams game with tickets she bought just days before she disappeared.

Anyone with tips for investigators is urged to call the Los Angeles Police Department’s Missing Persons Unit at 213-996-1800. Their off-hours and weekends number is 877-LAPD-24-7 (877-527-3247).

To remain anonymous, call Los Angeles Regional Crime Stoppers at 800-222-TIPS (800-222-8477) or visit their website.