claim rejected due to poor workmanship

<p>Good day</p> <p>my vehicle has been to the repairer for good period of time and had to go back. They replaced seal and bearing and propshaft where it fits into the gearbox and never replaced the gearbox oil there was only 50ml left in the box which Mayfair gearbox check in front of me. Now the gearbox has burnt out and the are telling me its ware & tare on the gearbox which caused it to burn out, which i doubt cause vehicle has only got 52 000km on the clock How do i go about this as they are saying this is my issue now where i fell i am fighting against iwyze and repairer. Please let me know best way forward with this issue </p> <p>Thanks</p> <p> </p>