My knowledge on this is very, very sketchy, but my understanding is the there is still a large amount of Russian gas transiting the Ukraine pipelines, Europe needs the gas so they buy it, Ukraine needs the transit money to defend against Russia so they keep the operation running. and Russia needs the gas money to attack Ukraine so they keep the operation running.
Honestly if true it is one of the weirdest situations I have ever heard about in the middle of a war.
I deliberately used an RT link because it is probably full of Russian propaganda and yet says basically the same thing as other articles. I originally learned about it via the Perun youtube channel(the best place to start if you want actual information not propaganda) but am unable to find the episode where it is mentioned.
https://www.rt.com/business/570805-russia-ukraine-eu-gas-tra...