Md. Code, Insurance § 2–204

(a) An order or notice of the Commissioner must be in writing and signed by the Commissioner or an individual authorized by the Commissioner.

(b) (1) An order of the Commissioner shall state:

(i) its effective date;

(ii) its purpose;

(iii) the grounds on which it is based; and

(iv) the provisions of this article under which action is or proposed to be taken.

(2) Failure to designate a particular provision of this article in accordance with paragraph (1)(iv) of this subsection does not deprive the Commissioner of the right to rely on that provision.

(c) An order or notice may be served on a person by:

(1) mailing it to the person at the last known principal place of business of the person, as listed in the records of the Commissioner;

(2) electronic means in accordance with § 2–116 of this title; or

(3) otherwise delivering it to the person.