KeepInventory doesn't work properly

[DeSkyno18]

So, I've got a survival world and I hate loosing all my items when dying so I want to keep my inventory after dying. The KeepInventory is set to true but sometimes I keep the inventory sometimes I loose it. Anyone know how to solve this? Also I've got the minepack plugin. When dying the Inventory in the backpack always remains, maybe the server goes in conflict with this plugin?

[_Tarna_]

keep inventory is per world so make sure you do the command in every single world you want it to work in. Also make sure you are doing the command exactly like /gamerule keepInventory true since it is case sensitive. 

[DeSkyno18]

Yeah I have only one word so that's not the problem but I'll try again. Thanks for the help.