What is happening in the Strait of Hormuz as Trump gives Iran 48 hours to open it?

Transit through Strait of Hormuz has slowed to near standstill, HT reported, citing MarineTraffic data. However, Iran claimed it's open except for vessels linked to its "enemies". Some ships are reportedly being charged up to $2 million to pass. US has given Iran 48 hours to reopen it, while Japan said it could deploy its military for minesweeping in Strait.