You apparently don't understand what the word, sanctions, means. The US did block the importation of Russian oil into the US, but if it had sanctioned the sale of Russian oil then any company anywhere in the world that purchased Russian oil would be banned from doing business in the US or using US financial systems. Clearly, the US did not sanction the sale of Russian oil.
According to both the Russian Prime Minister and Deputy Prime Minister, the sanctions have already put the Russian economy into a decline and put the Russian war effort in jeopardy, so clearly the sanctions are working.