At&t software update s5 not updating

[Henry503]

I have a at&t phone without the original imei number it's currently using cricket services I try to update the software but it says it's currently has the latest update which is KitKat 4.4.2 so can I update my phone to marshmallow 6.0

 

[B. Diddy]

Welcome to Android Central! You generally have to be on AT&T's network in order to receive their official OTA update. Otherwise, try using Samsung Smart Switch.