(CNN) Video surveillance footage taken outside Jeffrey Epstein's cell during his first apparent suicide attempt in July 2019 "no longer exists" due to an accidental mix-up and technical issues, the government said in a court filing.

Prison officers at the Metropolitan Correctional Center (MCC) in New York found Epstein on the floor of his cell in the early-morning hours of July 23. He was found with a strip of bedsheet around his neck in what a federal document calls an apparent suicide attempt.

Video from the cameras that were recording outside his cell was not properly preserved and no longer exists, according to a letter filed Thursday by the US Attorney's Office in the Southern District of New York.

On July 25, an attorney for Epstein's cellmate at the time asked that MCC preserve video from outside the cell, the filing notes. MCC legal counsel looked up the cellmate's cell number in the MCC computer system and requested that the staff preserve video of the cell from that night, the filing says.

However, the attorney said in December that security footage from that night was missing. The government responded a day later, saying the video was not missing and that it had been preserved.