One month after the battle over Lisa Marie Presley's estate was settled, it's facing more legal difficulties.

Naussany Investments & Private Lending, LLC a lawsuit Sept. 18 alleging that the late singer—the daughter of Elvis Presley and Priscilla Presley—failed to pay back a $3.8 million loan before her death in January.

In their filing, obtained by E! News, the company alleges that Lisa Marie took out the loan in May 2018 and used her ownership stake in Elvis Presley Enterprises and Graceland, her late father's former home in Memphis, Tenn., as collateral.

Lisa Marie had until May 16, 2022, to pay off the $3.8 million, according to documents provided in the lawsuit, or risk them filing the Deed of Trust that was signed and notarized under an agreement to pay off the loan by the due date.

Naussany Investments & Private Lending, LLC states in their filing that they had not had contact with Lisa Marie since March 2022 and that several of their letters mailed to her business address in the Los Angeles area were refused and returned.

The group says in the lawsuit they would agree to a potential settlement arrangement that would avoid further legal action if her estate pays at least 75 percent of the loan balance, or $2.850 million, within 45 days.

Lisa Marie died at age 54 in January from complications resulting from small bowel obstruction, County of Los Angeles Medical-Examiner records showed. Following her death, a judge approved her eldest child Riley Keough to become the sole heir of her estate and the new owner of Graceland, ending a legal dispute over her will that her mother had brought into question.

But despite the disagreement over the estate, Priscilla made it clear that she has nothing but love for her eldest grandchild.

"Riley and I are on good terms," she explained to the Hollywood Reporter in an interview published in August. "We were never not on good terms. That was all publicity. This is private and this is not something to fool around with and say that we're not agreeing."

E! News has reached out to a reps for Lisa Marie's estate and Riley and has not heard back.

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