Android app incorrectly shows Windows offline, but able to connect manually via ID/PW

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I'm attempting to control a Windows 10 machine using Team Viewer 15.12.4 (32-bit). I've been able to do this via another Windows 10 machine without issue. However, my typical use case will be to access via my Pixel 3 XL, presently running the latest public version of Android 11. On my phone, I have the latest Team Viewer app installed, version 15.12.12.

My Windows 10 machine shows up as offline when I view the list in My Computers. This is incorrect; it is online. I'm actually able to connect to the Windows 10 machine without an issue when I enter in the "Partner ID" and Password in the app, taken from my Windows machine while it happens to be in front of me. Using the codes here isn't practical long term; I only happen to be in front of the Windows machine because I'm troubleshooting.

Why isn't the connection showing up accurately for the Android app? When I ignore the "offiline" status and click "Remote control (using password)" anyway, it returns an error, "Could not connect to partner."

Guidance on next steps much appreciated.