Roku operating system updates gradually are rolled out unit by unit. Some get it early, some get it late, on a schedule only known internally by Roku. Until Roku decides it's your turn the manual update mentioned by Kariza won't show the update is available.
My three operating units became eligable for the current update to 11.5 on three different dates. Even multiple units of the same Roku model on the same account may get authorized at different times.
I'm never in a hurry to receive a new release. The later in the rollout I receive a new version, the more bugs will have been fixed before they have a chance to affect me.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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