why lg g3 ls990 sprint update centre isn't oppening?

[lg_G3user]

I have a lg g3 ls990 sprint and its on android os v.4.4.2 and i want to upgrade it to the v.5.0 or 5.1 ota and whenever i try to open the update centre app it doesn't opens instead the app update application starts so i need help please tell me a solution to my problem what should i do?

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[bar1203]

Are you trying to get the update from settings > system updates?

Posted via the Android Central App

 

[lg_G3user]

Yes i am trying to get the update ota from system updates

Posted via the Android Central App