GPS and data problems, can downgrade to Android 4.3?

[billybarrio]

Hi,
My name is Billy and I have got also a clone Note 3 as follows:

Model number : SM-N9006
Andoid Version: 4.4 (it says...)
Version: N9006ZCUBMI3
Kernel: 3.4.5-526212
Build number: JSS15J.N9006ZCUBMI5
CPU Type MediaTek MT6572 x2 1.3 Ghz
RAM 4 GB

Several things don't work of which (most importants):
No Data - No 3G
No contacts google account sync. Not showed in Sync Menu.

Is it possible to go back to 4.3 Android and if yes how? Are there ROMs available for this model?

Any other suggestions to have at least these two points working?

Thanks for any help

Billy