Problem with Unipower control unit

I phoned to have unit repaired as it was going into overload mode. One of my batteries had given in and died. This was explained and vehicle left there. Gawie worked on it now and then and replaced a relay which he said was faulty. As I was out the country the vehicle stood at their premises for over a month and when we phoned and wrote mails, we got no answer. My son collected the car and now 2nd battery had died. Since then I replaced both batteries, the vehicle has to be started 5 or 6 times before the unit will work properly. I have been phoning for over 2 weeks and leaving messages to phone me, writing mails and I get no reply or answers from them. I am totally irate