It means it didn't fetch any guide data from Pluto during that run.
You pasted the logs upside down (reverse chronologoical order). Look at the timestamps.
That's probably from an html dump of the logs in Synology Docker Station.
To see the error that caused it, you have to see what was logged before those two lines.
errors will appear here
|2024-02-14 09:45:44|stdout|mv: can't rename '*playlist.m3u': No such file or directory|
|2024-02-14 09:45:44|stdout|mv: can't rename '*epg.xml': No such file or directory|
|2024-02-14 09:45:44|stdout|Last ran: Wed Feb 14 09:45:44 UTC 2024|
|2024-02-14 10:03:32|stdout| - - [14/Feb/2024:10:03:32 +0000] GET /epg.xml HTTP/1.1 200 11949075 - Mozilla/5.0 ChannelsDVR+XMLTV/1.0 -|
|2024-02-14 12:45:45|stdout|[INFO] Grabbing EPG...|
A good fetch starts like this
2024-02-15T00:00:03.093774660Z [INFO] Grabbing EPG...
2024-02-15T00:00:03.117201760Z https://api.pluto.tv/v2/channels?start=2024-02-14%2016%3A00%3A00.000-0800&stop=2024-02-14%2022%3A00%3A00.000-0800
2024-02-15T00:00:03.140956768Z https://api.pluto.tv/v2/channels?start=2024-02-14%2022%3A00%3A00.000-0800&stop=2024-02-15%2004%3A00%3A00.000-0800
2024-02-15T00:00:03.143840046Z https://api.pluto.tv/v2/channels?start=2024-02-15%2004%3A00%3A00.000-0800&stop=2024-02-15%2010%3A00%3A00.000-0800
2024-02-15T00:00:03.145837091Z https://api.pluto.tv/v2/channels?start=2024-02-15%2010%3A00%3A00.000-0800&stop=2024-02-15%2016%3A00%3A00.000-0800
2024-02-15T00:00:09.775053797Z [DEBUG] Using api.pluto.tv, writing cache.json.
and ends like this
2024-02-15T00:00:38.465110026Z [SUCCESS] Wrote the EPG to epg.xml!
2024-02-15T00:00:38.489745331Z [SUCCESS] Wrote the M3U8 tuner to playlist.m3u!
2024-02-15T00:00:39.227440884Z Last ran: Wed Feb 14 16:00:39 PST 2024
If you use Portainer you can download the last 4 hours of the log to a file.
Or by using this docker command (and optionally redirect output to a file)
docker logs -t --since=4h pluto-for-channels 2>&1