game stores ...***** stores that dont play the game

Hi i have been a regular customer of game stores for many years .i bought a samsung microwave with a 10 year warranty on ceramic and 2 year warranty on the internals .It had repairs promptly done to it 9 july 2017 now it needs reapairs again in early april 2018 when my guarantee runs out in june 20-18.Game is saying a ****roach caused it to stop working .They refuse to repair it unless i pay r1800 while under guarantee ..thats the price i paid new ..more or less .Big corporate *****es .Management refuses to help me .