Mo. Rev. Stat. § 486.790: Resignation of notary commission.

1. A notary who resigns his or her commission shall send to the secretary by any means providing a tangible receipt, including certified mail and electronic transmission, a signed notice indicating the effective date of resignation.

2. A notary who ceases to reside in or to maintain a regular place of work or business in this state, or who becomes permanently unable to perform their notarial duties, shall resign their commission.