No signal on recording failure

Last week my one pass for The Americans didn't record. When I looked in history, it said no signal. Confused, since I didn't see any recording failures on my other roamio. But since this show is broadcast multiple times the same nite, I was wondering why it didn't retry? So even though the first recording failed due to no signal and there was no entry iin My Recordings, the later rebroadcasts were marked as a Duplicate. I know if a recording on an older 2 tuner premiere failed due to a tuner conflict, the later rebroadcast would record.
So why wouldn't a signal failure do the same?

Did anyone get a recording failure last week? I'm on Comcast in west Chicago.

Thanks