Who experienced the "Crude Oil Bao incident" back then?

US crude oil futures dropped to one cent, and someone bought ten thousand yuan worth.
Thinking to themselves: worst case scenario, I lose ten thousand yuan, just playing around for a bit of fun.
Who knew, half an hour later
crude oil futures plummeted, and they owed 40 million yuan.
Many people don't understand it, let me explain it:
At that time, the price was one cent,
ten thousand yuan could buy one million barrels.
Later the price dropped to -40.
At this point there were two options:
1, wait a few days for crude oil delivery, you charter a ship to haul one million barrels of crude oil.
2, sell off the one million barrel contract,
but because the price is -40,
you need to pay someone else 40 million yuan just to sell the contract.