When 25-year-old Amber Hilberling was found dead in her prison cell on October 24, 2016, her mom, Rhonda, and stepfather, Bryan, claim the prison left them a message on their cell phone, but hours passed before they learned what happened to their daughter.

“I call [the prison] and I get hung up on,” Rhonda claims to Dr. Phil in an exclusive interview airing Monday. “They wouldn’t talk to me.”

WATCH: Amber Hilberling’s Mom Describes Her Daughter’s Behavior Before Suicide 

Bryan claims when he attempted to find out more details from the Mabel Bassett Correctional Center, he was told, “’I have no idea who made that phone call. You’re just going to have to wait until they call you back.’”

Rhonda says after making multiple calls, someone at the correctional center finally told her, “She is dead.”

Rhonda says she thought it was a mistake when she heard the news about her daughter, who was serving a 25-year sentence, convicted of second-degree murder in the death of her husband, Josh Hilberling, despite her insistence that Josh’s fall through the window in the couple’s 25th-floor Tulsa, Oklahoma apartment in 2011 was an accident.

WATCH: Parents Of Amber Hilberling Say They Believe She May Have Been The Victim Of Foul Play

Bryan claims that after more than eight hours of calling the prison and trying to get someone on the phone, he finally got someone to speak to him. “The only thing I got was, ‘We’re calling it a suicide,’” he says. “They wouldn’t give how, what happened -- any details whatsoever.”

“We found out that she hung herself on the news,” Rhonda adds.

Watch the video above to hear about a social media message Rhonda claims a relative of Josh’s posted after Amber’s death. And on Monday’s episode, hear why Rhonda and Bryan say they believe Amber may have been the victim of foul play. Check here to see where you can watch.