Applies to: All Reolink cameras and NVRs.
"Playback" option is only for playing recordings stored in Micro SD card or HDD inside NVR. If you use a camera with no SD card (e.g. RLC-410) or not connecting to NVR that is built with a HDD, then "Playback" option won't be used in your case. For more info, please refer to: https://reolink.com/faq/remotely-playback-record-on-via-reolink-client-from-sd-card-or-nvr/
Note: The RLK4-211WB4-S support both Micro SD card and HDD recording. But the Micro SD card will record only when motion is detected.
For recordings stored on your PC HDD or external HDD, you can go to the folder and find the video files, then double-click to open with media players.
If you don't know where the local recordings are stored on your PC, you can refer to the link to find out Record Path,
How to Set Local Record Schedule via Reolink Client(New Client)