Lazada store link :
Instruction :
1. Jailbreak muna sa Checkrain
2. install cydia
3. open cydia and install “Apple File Conduit 2”
4. Connect iphone to PC and open 3utools
5. in 3utools click iDevice tab menu and open “File/File System (Jailbreak)/System/Library/CoreServices/SystemVersion.plist
6. edit ProductBuildVersion and ProductVersion
7. click Save
8. Restart phone before unlocking using gppsim ICCID METHOD