With the error message'EKF2 IMU0~1 ground mag anomaly, yaw re-aligned' The drone showed a toilet bowl phenomenon

I built a quadcopter and made my first flight. However, the drone crashed while showing a phenomenon similar to the toilet bowl with the phrase’EKF2 IMU0~1 ground mag anomaly, yaw re-aligned’ on the HUD window… I don’t know. Please help me with the meaning of that error message. Additionally, in fact, the airframe’s motor & transmission has very tight specifications. The log is attached, so please analyze it.https://drive.google.com/drive/folders/1GHRVm_8kveEx50vtW-PCNPkC9m4o1Til

That log has an access request. Remove that for help.