Waiting for a Clearance Letter

Since waiting a max of 72 hours for a clearance letter to be issued after request, i find myself phoning a further 6 times more to ask for this. Each time the agent informed me that it has been escalated. There appears to be an issue with this escalation process. If there is a problem in getting this done i am not informed. I am denied a chance to talk to a team leader or manager to ask for help