Faulty LG Microwave

I bought a LG 40lts combo microwave (grill and microwave),which is just over two yrs old.in June/July had to this year it was 1abd a half yrs old had to send it to replace the Magnetro and then 6months later just when the 2yr warranty expired the magnetron need to be replaced again and now they want me to pay.i understand warranty expired ,but why magneton fault so many times within the 2yrs,and LG is no help at all will not recommend LG to anyone.we spend so much money in brands we believe are good just to be let down.