On now thumbnails broken

The thumbnails on the "on now" tab of the app are broken, except for a few, generic station logos.
They are broken on the iOS app, on the web interface, and the FireTV app.
The 2-week guide is intact.

My server is run on a Synology NAS.
The only thing that could remotely have caused this was removel of the UPnP in favor of manual port forwarding, but I doubt this was the reason.

Could I be experiencing the same problem described here: All thumbnails are missing today - #40 by Senorbeau

Since nobody replied to you, I think this might fix it.
In the directory where Channels DVR records to there is a folder named Images and within that folder is one named tmsimg Rename the tmsimg folder to tmsimg.old
If that works you can delete the tmsimg.old folder
If it doesn't work you can rename the tmsimg.old folder back to tmsimg

Unfortunately, it didn't fix it.

My issue turned out to be my NAS lost connection to the internet. Rebooting it fixed my problem