Tablet in for repairs

Good morning on the 05/09/17 i have given my tablet in for repairs because of the fact that it stopped working and it was still under guarantee but i am still waiting for them to send it back with a solution and when i query it they just say that they are still busy with it and i must wait i dont understand that if a product is under guarantee why they dont just replace it.

Verry unhappy with the service.