The current circulating amount is 508 million. I would like to ask why the total balance plus the staked balance is only 448 million, where did the other 60 million go?

The amount of coins at the exchange address is decreasing, while the amount of coins at the staking address is increasing. Now is the least wise choice to go short. $USUAL
If you want to hedge after staking your spot, you should go short again at a high point, not now.