Bad service

My car had a back fire and it was found that the injectors was the problem. My claim was approved but the service provider discover that the engin needs to be rebuild A new quote as per insurance was sent . After all the documents was sent auto and general request a combinef quotation. They went quite. I phone everyday sent mails 3 times a day. They read the mails but don't reply. Today after more than 2 months I receive a call from James who told me they are only paying R32 000 instead of the R74 000 which was the combined quote. He also said The service provider must decide what they want to fix. They are clever requesting a combined quote to to pay a portion. .