https://www.gamespot.com/articles/nba-2k18-update-out-for-release-day-addresses-lost/1100-6453408/

Ahead of its official release on September 19, NBA 2K18 landed in the hands of everyone who pre-ordered it last Friday. Unfortunately, a number of players have encountered various bugs, the most serious of which causes Xbox One players' MyCareer save data to be lost. A patch is on the way, but 2K has recommended players on Xbox One to avoid the mode altogether until it's available. [Update: The patch is out now, but 2K says more details on it aren't coming until "later."]

NBA 2K18 officially launches on September 19 for PS4, Xbox One, PC, and Switch. The Switch version requires you to have a micro SD card, and it notably only runs at 30 FPS, as opposed to the other console versions' 60 FPS.