hTC desire 816w update problem topic

Hi i bought desire 816w, it cames from china . i saw many people using HTC sense v6 but i got 5.5 . when i try to update from phone ,,, it says its already updated. is there anyway to update HTC sense 5.5 to 6.0 ???
Thanks


Android Version : 4.4.2
HTC SENSE version : 5.5
Software Version : 1.0.0D816w
HTC SDK API LEVEL :5.69
Kernel Version : 3.4.67k3@k3-desktop#1Mon Nov17 15:43:20 CST 2014
Baseband Version : MOLY.WR8.W1315.MD.WG.MP.V34.2014/11/08 10:07
Build Number : ALPS.KK1.MP1.v2.10