AUDI MENLYN FAILING TO DIAGNOSE

My audi Q7 (BB60RH GP) has been at Audi Center Menlyn for more than 2months now. Initially they said the problem is a steering lock and needs to be replaced, which I paid a deposit of R7500 for work to be done. when that was done they say all the locks need to be replaced which even when it is nonsensical I gave a go ahead. still after that they are failing to code it.<br> Even my warranty consultant refused to pay steering column cause of this poor and miss-diagnoses