how does that even happens

Tell e more.

it was a minor glitch cause by the y2k bug! no one was hurt and no radiation escaped, but japan experienced alot of these glitches at various nuclear plants. their computers were most likely processing the computing change from 1999 to 2000 and stopped for a moment

Fascinating. Gimme more of your eternal knowledge.

hmmm oh some other y2k glitches cause they're actually so funny: an 105 year old woman was automatically offered daycare in january 2000 because her age showed up as five! in denmark, a baby born on jan. 1 was recorded as 100 years old, and a german bank accidentally transferred $6.3 million dollars to some random guy, he didn't get to keep it though

there were some not so funny ones too like 154 pregnant women in the uk being given incorrect down syndrome risk assessments

That furst one is hilaruous, yhe second is dwvastating.