Month after month we get BAD service and late payments from the Rental departments of Jawitz Properties Amanzimtoti

Jawitz Properties, Amanzimtoti has the lease agreement between us and our tenant (That they {Previously Maxprop} introduced to us from Sept 2012) We have proof that our tenant pays every month his rent before the 7th, as per lease agreement But Month after month we receive very late payment of our money and we have to phone them to ask for payment! For this month - January 2018, up untill today, 24/01/2018 we haven't received our rent! When you phone - they pass the bucket from one to the other - then it is the rental agent, then you must speak to the principal and owner { John Arnold}, and he will then say he will speak to his wife {Jenny} who is doing all the payments. Really it is the worst Estate agent! Two months ago, we even phoned the head office of Jawitz, who is handling the franchises, and their pathetic help was to send an email to the principal {John}, requesting him to phone us! That he obviously did NOT do! Please help, what can we do? They take their percentage ever month for admin fee! Whenever there is a problem at the house the tenant call us direct, and we will sort out or arrange for somebody to repair what is needed - They do not deserve any admin fee for this Lease agreement! Jawitz keep the money in their account for almost 20 days, surely they get interest on our money!