(a) Licenses issued under the provisions of this chapter may be revoked by the Mayor after notice and hearing, for any of the following causes:
(1) Fraud, misrepresentation or false statement contained in the application for license;
(2) Fraud, misrepresentation or false statement made in the course of carrying on his business as solicitor or as canvasser;
(3) Any violation of this chapter;
(4) conviction of any crime or misdemeanor involving moral turpitude; or
(5) Conducting the business of soliciting, or of canvassing, in an unlawful manner as to constitute a breach of the peace or to constitute a menace to the health, safety or general welfare of the public.
(b) Notice of the hearing for revocation of a license shall be given in writing, setting forth specifically the grounds of complaint and the time and place of hearing. The notice shall be served personally upon the person or mailed, postage prepaid, to the licensee at the last known address at least five days prior to the date set for hearing.