Default [Q] S4 GT-I9500 custom to official??

Im using Samsung Gt I9500 in india. I rooted my phone & after that in download mode following message shown

odin mode
Product name : GT - I9500
Current Binary : Custom
System Status : Custom
Knox Warranty Void : 1
AP SWREV : A2

However i tried to fix it & current status is

odin mode
Product name : GT - I9500
Current Binary : Samsung Official
System Status : Custom
Knox Warranty Void : 1
AP SWREV : A2

Im unable to get OTA update due to modification. Is there any way to change system status to official & after that can i receive OTA or is it necessory to change knox warranty status to 0, if it is then any solution for it??

Need help!!!!!!

Android version - 4.3
Baseband Version - I9500DDUEMK9
Kernal Version - 3.4.5-2092849
Build Number - JSS15J.I9500XXUEMK9