Any taxicab license may be revoked by the Manager at any time for cause and shall be revoked for any of the following reasons at the discretion of the Manager after a public hearing and after first giving five days notice of said hearing to the holder of such license:
(A) Failure of any operator for 30 days to pay any final judgment recovered for damages arising out of the operation of said taxicab;
(B) Whenever any operator shall fail to operate any such licensed taxicab or taxicabs for a period of 30 days, unless prevented by an emergency over which the operator has no control.
(`89 Code, § 123.140)