REX DIFF AND GEARBOX POLOKWANE

We outsourced service from RDG Polokwane to assist in Diff recon, we agreed on a payment amount of R10925 for the repairs. The money was paid in full upon collection of the Diff. We took the Diff to our workshop, it was fitted and Lubricated. The customer was driving to Durban, as he was passing Joburg, he noticed that the vehicle has an Oil leak from the Diff and he reported the Leak immediately to us. I contacted RDG and they never got back to me. I advised the customer to fill up the Oil as he drove back to Polokwane. As soon as the customer brought the car to my workshop, I took it back to RDG to check the problem of the Diff (and this was only 2 days after collecting the diff from them). They called us after a short while and said the propshaft was not balanced. Then I went to their workshop to find out exactly what happened, so they told us there was never oil poured in the diff, the problem was not caused by the propshaft. So then we asked them how there was an Oil leak if there was never Oil poured in the diff and IF there was no Oil in the Diff was the vehicle going to be able to drive from Polokwane to Durban and back? So they rechecked the Diff and sent us another quote for the same thing that they claimed to have fixed before, the quote was now R9200. They said they will not take responsibility for that issue because of the lack of Oil. After, we told them we will provide the parts and they will just do the fitting. Then as I was driving on the way to buy parts, I got a call from one of the management there saying ''My place is not a playground you must come back and take your ****ING car and **** Off!'' He said it exactly like that. So we took the vehicle to another workshop where we paid another R10 600 and they replaced the parts that were not replaced by RDG hence they never gave me the old parts back. So now I demand my money back from RDG, because they did not fix anything and they are ******S, they know I'm just a poor black woman they can just tell me where to get off and get away with it! I am also running a workshop and this is not how we treat our Clients!