I've still got a Nokia 3 which isn't used anymore but last time I used it , it was on 8.0.0 and June security.
Mines the unlocked TA-1020
It wouldn't find an update until I cleared the cache of Google services framework, took the SIM card out then rebooted and connect to WiFi for an update search, then it found it, I then reinserted the SIM .
Again I'm not sure if this is why it worked or it's just Nokia and their half arsed way to doing things .
I went back to Apple because they at least allow updates across the range of compatible handsets from day one of update release