Replace pattern not working

Text: S(\d\d)E
Replace with: s\1e

doesn't change or replace case. I am using the regular expression and Case sensitive checked and unchecked.

TVShow (years) 1080p S01E01 EpisodeName
to
TVShow (years) 1080p s01e01 EpisodeName

Any ideas?

B.T.W. PLEX understands the lowercase now and I find it easier to read

FIXED -----My Error Copied \'s as /'s

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