Iran has claimed the downing of Ukrainian passenger jet in January was due to a "misalignment" of the air defence system's radar, i24 News reported.
The Iranian Civil Aviation authority claimed "A failure occurred due to a human error in following the procedure" for aligning the radar, causing a "107-degree error" in the system.
A Ukrainian passenger jet was downed by Iran during a retaliation strike on American airbases in Iraq to avenge the death of former commander of the elite Quds Force, Qassem Soleimani on January 8.
The Boeing 737 was struck by two missiles, killing all 176 passengers and crew.
After a few days and global outrage, Iran finally took responsibility for the incident.
The Iranian government agreed to send the black box of the plane to France to be studied independently, which will reveal the final moments of the plane before the missiles struck.
Iran has said the delay in sending the boxes was caused by the coronavirus pandemic, which has seen most international flights to France cancelled.