Mo. Rev. Stat. § 107.040

If, upon investigation of the matter, it shall appear that any surety has become a nonresident of the county in which the bond is filed, has died, become insolvent, or in any otherwise insufficient, the court shall require the officer for whom such surety executed the bond to give additional security by a day named; and, in default thereof, the said office shall be forfeited, and the same shall become vacant, and the facts shall be certified to the court or officer whose duty it is to fill such vacancy.