Windows 10 Game Freezes with Blue Screen Termination Code UN

The computer froze twice while gaming, accompanied by a buzzing noise from the speakers. The case's power button failed to shut down the system (ultimately requiring a hard power-off by unplugging the power cord). After the first freeze, it automatically restarted when plugged back in. Shortly after resuming gameplay, it displayed a blue screen with stop code UN, and the restart progress bar became stuck. Please advise on the cause of the malfunction and the solution.