Technicians keep 'undispatching' themselves

Logged a fault with our line on the 11/08/2017. reference no. 614CNK110817. Had contact from a technician on the 18/08/2017 who said he was coming to our complex to check it out. He never arrived. Called your call centre on the 23/08/2017. Call centre agent was helpful and went through the history. What he found is that over five different technicians had been assigned the fault but they all has subsequently 'undispatched' themselves from it. It seems that the technicians have no interest in dealing with our interest and purposely remove themselves after being assigned our fault?? Call centre agent escalated our fault and the reference no. is 999889. Such disregard must result in those technicians being disciplined. Please can our fault be rectified ASAP.