Do you not understand how contracts work? They're frequently used to bankrupt people and countries when the terms are violated unless there's reason to allow renegotiation of the terms. Do you think it possible that waging war might be considered a reason to be unforgiving with the terms?

The contract was in dollars. Not rubles. That's how business is conducted.

Russia is trying to get around the EU's sanctions by trying to force payment in rubles for Russian gas. (Those sanctions are completely justified. Russia invaded a European country, and is carrying out a bloody genocide there.) The EU refused to render its own sanctions toothless, so Putin retaliates by threatening to cut off the EU's gas supply. In other words, Putin is trying to extort a capitulation from the EU. Another word for extortion is "blackmail."

Putin's blackmail is apparently not going to work. The EU is not buckling. They are prepared to do without Russian fuel. This is a good thing for two reasons: (1) Putin will be deprived of an important revinue source, making it more difficult for him to realize his imperial fever dream of denying the Ukrainian people of their right to exist. And (2) cutting off the gas supply will spur movement toward green energy sources like solar, wind, and geothermal energy. We are hurtling toward a climate catastrophe, and this will help us avoid a global disaster. Gotta love it!