Missing Recordings

Our Cox DVR is not recording shows that have been scheduled for recording.  A quick look at the guide reveals the red circle, indicating these shows are designated for recording, yet they are not being recorded.  This might be because of recording conflicts, but I do not see any way to understand whether this occurred, either by some type of "notice" or reviewing a "missed recordings" tab.  It seems as though the Cox receiver should tell you if there is a scheduling conflict.  I am not sure what to do.