Lindsay and Dina Sue Fox News Channel We Didn't Do Coke Together!

2/2/2015 2:00 PM PST

Lindsay and Dina Lohan -- Sue Fox News Channel ... We Didn't do Coke Together!

TMZ has obtained letters Fox News Channel sent to the lawyer for Lindsay and Dina, informing them an apology had been made on air, and FNC would send them a DVD of it. That letter was sent a year ago. Another letter was sent stating the segment would be removed from the network's website.  
A rep for FNC says when they sent the letters, "the Lohans did not make any demands for money, and we are surprised they are doing so now."
 and Dina Lohan have sued Fox News Channel and Sean Hannity claiming they were smeared on the network when someone on Hannity's show claimed LiLo and Dina snorted coke together.

In the lawsuit -- obtained by TMZ -- there was a discussion about recently deceased celebs, including Philip Seymour Hoffman, regarding celebrity drug use. The panel was discussing who might die next.

Michelle Fields said, "Lindsay Lohan's mom is doing cocaine with her" -- insinuating Lindsay would be the next to go.

Lindsay calls it "malicious innuendo." For the record, she's admitted to doing coke. She also claimed her mom was on coke in a hysterical call she made to her dad in 2012.

The discussion occurred in February of last year, just days after Hoffman's death.

LiLo and Dina claim it was "a direct smear on the character/reputation of Lindsay and Dina."