What kind of episode title is "The Polio Crusade originally aired in 2009"

I'm serious; that is not an IMDb episode title. If it is not already in IMDb, it should be added to the correct season in 2009.

The problem is that it already exists in IMDb:

https://www.imdb.com/title/tt1347564/?ref_=ttep_ep2

episode 21.2, aired 2 February 2009.

For the offending episode:

https://www.imdb.com/title/tt23456754/?ref_=ttep_ep_cur

I submitted a merge by the standard procedure of submitting correction of episode title and number to match the original episode.

Here is my accompanying "Explanation:"

This episode indeed premiered in 2009 and it is already in IMDb. I am submitting this as a merge.
Here is PBS American Experience page with "The Polio Crusade" listed as Season 21:
https://www.pbs.org/show/american-experience/

I submitted this back on November 19

#221119-061813-208000