"There was a problem saving channel mappings. Please try again."

[Nitro981]

Server Version#: 1.41.6.9606
Player Version#:
Tuner Make/Model: HDHomeRun PRIME
Guide/Lineup name: Fios
Using XMLTV?: No
Channel number/Name:

I am attempting to setup my tuner in Plex. Plex finds the tuner immediately, sees the channels, and maps all of the guide listings. When attempting to save, I get an error that there was a problem saving channel mappings.

This error persists whether I try to save from my local Plex instance (running on Docker) or from hosted interface at app.plex.tv. I can save individual channels if I try one at a time, but I cannot save the entire guide.

[pshanew]

Ensure you don’t have the same guide data (EPG channel, right-hand column) mapped to more than one tuner channel (left-hand column) in the channel mapping dialog. If you do, it will fail to save since each EPG channel can only be used once.

[Nitro981]

I checked that, too. Every channel has a 1:1 mapping from the guide.