Why am I unable to update my system software?

[Shinju R]

I cant update my system softwear

I am using HTC desire 820 dual SIM. A week ago I got notification about android 6 update. It's a two section download , first part is 75 mb download second one is 1.06 gb . I downloaded the first file and installed it. The I got another notification of second part. I chose remind me later.second day I just try to update my phone its show "your phone is up to date".
Please help me to update my phone.

 

[B. Diddy]

Welcome to Android Central! Sometimes, if you ignore or defer an update, it'll put you at the end of the queue again. Wait a few more days to a couple of weeks to see if it pops up again.