OnePlus
Manually Check for System Updates auf OnePlus
OnePlus phones show a system update notification only once, right after the update becomes available for your device. If you swipe it away or clear your notification history, the alert is gone for good and the phone will not remind you again on its own.
The update status lives inside the System updates section of the Settings app, which checks in with OnePlus servers every time you open it. That means you can trigger a fresh check manually at any point instead of waiting for a push notification that already passed.
Open Settings, then tap System, and select System updates. The screen shows your current OxygenOS version and immediately looks for a newer build. If one is available, you get the option to download and install it right there.
If the screen reports that your software is up to date but you expected a newer version, the rollout may not have reached your region or device variant yet. Regional and carrier-specific rollouts can lag behind by days or weeks, so checking again later is usually the better fix rather than digging for hidden settings.