Bungie took the server of Destiny 2 down after it was the latest hotfix patch created problems. Some players reported that their in-game currencies nad materials have disappeared. Soon after that, the servers went offline.
This is not the first time the game have had currency issue and the last time, the server was also turned off while Bungie figured out the issue. Bungie later came out to tweet that they will be keeping the servers offline to rollback player accounts back before the latest hotfix was released.
At that time, Bungie estimates that the server will only go back up at 7 pm PT on the 12th of February but it actually came back online a few hours earlier than that. The game was rolled back to before the Hotfix 220.127.116.11 update which means if you have purchased any Silver after that time, it will not be counted.