https://www.gamespot.com/articles/pubg-xbox-one-update-out-now-here-are-the-patch-no/1100-6459386/

PUBG Corp. has released a new update for the Xbox One version of PlayerUnknown's Battlegrounds. Patch #15 is available to download on the console now, although it's fairly minor as far as updates go, primarily focusing on bug fixes and other improvements to the game.

Among other things, PUBG Corp. has implemented a new system to report players who kill their teammates. After a team kill, players will be able to press Y on the result screen to bring up a "report" button, then press A to report the player in question. The report prompt will not appear if it wasn't a team kill.