Mo. Rev. Stat. § 140.140

The collector shall make diligent endeavor to collect all taxes upon said back tax book, and whenever he finds that any taxes therein have been paid, he shall report that fact to the county commission, or other proper officer, giving the name of the officer or person to whom such taxes were paid; and he shall also report to the commission, or other proper officer, all cases of double assessment or other errors, and thereupon the commission, or other proper officer, shall cause the necessary action to be taken and entries to be made.