Even though Destiny 2 is one of the biggest game launches of the year and has racked up a rather large player-base in such a short amount of time, there are still some major bugs you will probably want to avoid if you plan on enjoying your time in Bungie's sci-fi universe.
According to Gamespot, there's a bug involving the Postmaster where certain necessary items do not get sent to the Postmaster after completing a specific mission, causing it to glitch for some gamers and ruining their gameplay experience.
The problem is basically that there's a bug where if your inventory is full and you complete the "Enhance" quest, you will attempt to receive the MIDA Mini-Tool but it will not go into your inventory. Typically, what's supposed to happen in Destiny 2 when your inventory is full and you receive a quest item, it will go to the Postmaster. However, in this case, the MIDA Mini-Tool is not going to the Postmaster.
Bungie verified that this is also happening to quest rewards involving the Man O'War, and that players are simply losing these items after completing the quests.
In order to fix this problem your first step should be to clear out a space in your inventory for an energy weapon, if you're attempting to do the "Enhance" quest.
It's probably best to clear out the space before you complete the mission. The same applies for your heavy weapon slot as well, so this way when it's time to receive the quest rewards your inventory won't be full and you won't lose the items to the ether.
For now it's rather simple fix to this problem, which shouldn't inconvenience players too badly. On the upside, Bungie is already looking into the issue and attempting to get this bug fixed as soon as possible.
There's also another bug that has been specifically plaguing PS4 Pro owners, where Destiny 2 has been hanging up and locking up on them. Sony recently announced via a tweet that the support staff would be working with Bungie to fix the issue and likely roll out a patch to address the PS4 Pro locking up while playing the game. Don't be surprised if Bungie is likely collecting most of the biggest glitches, bugs and hang-ups currently affecting Destiny 2 and will address all of them in a single patch.
So far, the locking up and the quest reward bug appear to be the two biggest issues affecting gamers at the moment during the early goings of Destiny 2's launch. That's actually good news considering that usually games go through some fairly massive hiccups and hang-ups when launching, but this time things were fairly smooth, barring the server queues of course.
Again, if you're having issue with the inventory bug, just make sure you keep some weapon slots free so you don't have to worry about losing the quest rewards for now. I'm sure there will be a patch available either later in the week or sometime next week to address all the issues.