Contour will not record anything on PBS 804. I follow the usual procedure but when I check on future recordings it’s not there.

As Tiffany's troubleshooting suggested, you should verify you don't have a scheduling conflict with higher priority programs.

Could you have scheduled "New episodes only" and a missed program was not new? 

In some markets, the Guide will display multiple channels for the same network.  Normally, scheduled recordings on those channels will be indicated on each of the channels.  For missing future recordings, check the other channel to see if the recording is indicated on one channel but not the other.

You indicated you're unable to record anything on the PBS channel.  Are you able to watch that channel with live TV?  If not, you may have a poor signal.  Equipment issues can affect the signal for an individual channel or multiple channels, but not necessarily all channels.

If the missed recording was actually for just a specific program, try the following:

Use procedures for Managing Contour Scheduled Recordings to select the scheduled recording that didn't record.  If you're able to change its recording options, the entry isn't corrupted.  But, if you get an error message, delete the scheduled recording and re-create it from the Guide.