Happens with Revive as well. Restarting seems to work. If not, try going into services (start menu>run>"services.msc"), finding oculus' runtime, and restarting it.
If there's a management popup window akin to SteamVR for oculus, just try restarting that. Again, I've only had these solutions work on Vive.
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If there's a management popup window akin to SteamVR for oculus, just try restarting that. Again, I've only had these solutions work on Vive.