Expected: 301, Found: 200 for PDF file redirection.

I’m trying to redirect
https://www.clartelighting.com/wp-content/uploads/2020/10/DMX_Installation_Sheet.pdf
to
https://www.clartelighting.com/wp-content/uploads/2021/05/DMX-Installation-Sheet.pdf
but every time I enter the two URLs into the Source and Target fields and hit the Save button it automatically changes the Source URL to
/wp-content/uploads/2020/10/DMX_Installation_Sheet.pdf

Then when I click Check Redirect I get:

Expected: 301 to https://www.clartelighting.com/wp-content/uploads/2021/05/DMX-Installation-Sheet.pdf

Found: 200

Agent: Not using Redirection

I’ve tried clearing cache, I’ve tried re-entering the information, I’ve also tried the different Query Parameters settings but I still get the same error. Do I need to delete the source PDF from my media folder? Any help is appreciated.

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