The Minister may revoke an authorisation where -

(a) the person so authorised requests that his or her authorisation be revoked,

(b) following a notification under section 18 the non-compliance has continued after the time allowed to rectify the situation or, notwithstanding that the non-compliance has been rectified, the notification is a third or subsequent notification in respect of the same authorisation, or

(c) the Minister determines that the person so authorised is no longer, having regard to section 12, a fit and proper person to hold an authorisation.