Russian troops, meanwhile, have had their mobile phones confiscated by commanders — a lesson from its covert invasion of Crimea in 2014, and intended to give Russia greater control over information. Instead, it left a vacuum that was filled by Ukrainian content. Moscow is also hamstrung by its domestic need to maintain the fiction that the war is a limited “special operation”, meaning it cannot pump out images of Ukrainian losses on TV that might indicate otherwise. The Kremlin has nevertheless repeatedly insisted its operations are going to plan. “I have seen no evidence that its overall intent has changed,” said one western defence official.
Source. https://www.ft.com/content/0be1bc1a-6a9e-4ae0-b7d2-1d31018f14ca
That's just another way they exert control over facts they find inconvenient to their illegal aims.