Even before the war, my mother went to live in Russia and transferred her pension there

Even before the war, my mother went to live in Russia and transferred her pension there. She has a "residence permit" in Russia, is currently there and receives a pension. But, remaining a citizen of Ukraine, she has a great desire to return. How to transfer pension payment to Ukraine? The postal service for transferring the pension case does not work. Is it possible to personally bring the documents and give them to the pension fund? Will they accept these documents in this way?