A United Airlines Boeing 787-8, operating flight UA613 from Lagos, Nigeria, to Washington Dulles, experienced an unexpected loss of altitude while cruising over Ivory Coast on January 23, 2025. The aircraft, registered as N27903, was carrying 245 passengers and 11 crew members at the time of the incident.
No word on why it happened yet.
Just the usual hypothesis in AVH comments
https://avherald.com/h?article=5233baba&opt=0