The District of Columbia Organic Act of 1871

I look into the District of Columbia Organic Act of 1871 and read through the document. The District of Columbia had been known as a Municipal Corporation since 1802. How was that designation changed? Could it have been an "organic" act in 1871, if the District of Columbia was already a Municipal Corporation dating back 70 years prior?

Links:

https://www.nationallibertyalliance.org/two-us-constitutions

https://mainerepublicemailreport.com/2020/07/05/the-act-of-1871-was-repealed/

https://www.loc.gov/law/help/statutes-at-large/41st-congress/session-3/c41s3ch62.pdf

http://www.teamlaw.net/DCOAeffect.htm

https://americannationalmilitia.com/the-organic-act-of-1871-with-notes/

(1802 Washington D.C. Incorporation Documents)
https://catalog.archives.gov/id/10488163