I was already a Commissioned Army Officer but resigned my Commission. Do I have to attend the Direct Commissioning Course?

Prior-service Commissioned Officers, discharged from any military service, can apply for the USAR Reappointment Selection Panel through U.S. Army Reserve Careers Group (USARCG) at usarmy.usarc.usarcg.mbx.hq-ops-spcmsn-organizationalmailbox@army.mil.