The change was part of Update 1.1.2 that went live in the game on Tuesday, which was meant to reduce the amount of XP required to earn an Illuminated Engram from 160,000 to 120,000. However, fans quickly noticed that the change did not take effect and actually increased the XP required for rank-up all the way to 240,000.
Bungie’s dmg04 replied to the concerns on Reddit, giving an update that the problem had been solved in-game:
The good news is the XP bug has been fixed in-game so while trackers like Destiny Item Manager may show a different number it is only taking the intended 120,000 points to rank up. However, Bungie says that the API will continue to display the rank up goal as 240,000 XP and it won’t be fixed until a HotFix is deployed. The good news, though, is Bungie says that could happen as soon as tomorrow:
With Iron Banner being active this week, it will be good to have XP gains working as intended so that players can earn their Illuminated Engrams while grinding through the temporary, week-long PvP event. Moreover, when the Crimson Days Event launches in February players will want to make sure everything is clear while unlocking the new items.
Destiny 2 is available now on PC, PS4, and Xbox One.
Source: DTG Subreddit