https://www.vice.com/en_us/article/5dgw48/spacex-starlink-satellites-destroyed-by-geomagnetic-storm

Almost all of the 49 ​​Starlink satellites that SpaceX launched from Florida’s space coast on February 3 are crashing and burning up, after a geomagnetic storm knocked them from orbit.

Geomagnetic storms are triggered by disturbances on the Sun, such as a solar coronal mass ejection or unusually high-speed solar winds. These storms create disturbances in the Earth's magnetosphere—in the storm that SpaceX said took out its satellites, the atmosphere warmed and became dense, keeping the satellites from reaching a higher orbit to escape and stay aloft.