No person can receive credit for service under this subchapter unless:
(1) the person's military service was terminated by release from active duty or discharge on terms not dishonorable;
(2) the person does not receive and is not eligible to receive federal retirement payments based on 20 years or more of active military service or its equivalent; and
(3) the person does not have and does not receive credit for the service in any other public retirement system or program established under laws of this state.