The Division 2 had an emergency server restart yesterday which forced the servers to go down for a short while, and as explained by community developer Chris Gansler, this was in order to deactivate daily and weekly projects.
This is because there's been an issue that allows these projects to give their rewards multiple times, and while they work on a fix these have been disabled, hence why there was such short notice with the update as well.
What's more is that other players have been noticing issues with Signature ammo drops, and Ubisoft is aware of this problem. Players have reported losing all special ammo and receiving no drops after matchmaking, as also discovered on Reddit.
Have you encountered this issue in The Division 2?