Recent update of PUBG Mobile is the reason why the game was offline.  

Being offline  from 00:00:00 to 07:00:00 (UTC) on 15 OCT 2019 for maintenance, developer Tencent Games has recently released a new update 0.15.0 for PUBG Mobile on iOS and Android.

The developer treated their gamers with many cool updates: BRDM-2 Amphibious Armored Vehicle, Graffiti, Desert Eagle (weapon),  Fuel Drums and Ledge Grab, Vehicle Repair Packs . Fans will be able travel on land using upgraded gun-exclusive tanks, by sea or air using a helicopter and fight  enemies in mid-air.

If a player is new in this game a new heavy weapons are available for you: MGL Grenade Launcher, RPG-7, M3E1-A, M79 Grenade Launcher and M134 Minigun. Also these weapons can be revived by picking ID cards of your teammates. Fuel Drums and Ledge Grab allows you to make vehicle gasoline containers explode by shooting several bullets at them.

Additionally to the classic battleground and undead makeover players can enjoy new Payload Mode and Survive Till Dawn-Halloween Mode with thematic monsters. 

Beside new features a gamer will get a prize such as Fairy Set, 50 silver Fragments and 2,888 BP, if a game is updated before October 22nd.