False hope on vehicle policy

I am not happy with old mutual , it has been over a month for them processing my vehicle claim , the car has been written off , they asked for all the documents and I provided them with the documents , they also requested for vehicle registration certificate as I own the vehicle , 2 or 3 days after the certificate was collected from me they phoned to advise me that the car that had the certificate was hijacked so they will send me email regarding the payment of 80% and 20% , They said they will pay 80% while waiting for the duplicate certificate and 20% will be paid once they have the duplicate , I did not agree to it , I told them I need full payment as I need to buy another car as the car is important for my family , after that they said they are waiting for SIU report , it has been over two weeks waiting for the SIU report and what worriers me is that they told me about the 80/20% payout and the story changed to SIU report , they gave me a false hope

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