Cannot play internet streaming content from a channel on iOS - Could not direct play or transcode

I’m trying to play content on my iOS from a Plex channel that streams TV over the internet.

I get the error message:

"Could not create the playback session for this item

Could not direct play because: App cannot direct play this item. No direct play profile exists for protocol http, with container MP4, and video codec H264.
Could not transcode because: Cannot convert this item. No conversion audio and video encoders could not be found in app profile."

In the server logs i get similar messages:

“no direct play video profile exists for http/mp4/h264”
“no direct play video profile exists for http/MP4/H264/AAC”