Magnetron warranty

Good day,<br> I have been trying to get information regarding an LG microwave oven we got as a wedding present in 2011. The magnetron broke last week and as I understand, it is still under the 5 year warranty. The problem is that I don't have proof of purchase as this was a wedding gift. The one consultant tells me that it is only a 3 year warranty, but according to the sticker on my microwave and the user manual it is 2 + 3 years (5 years for the magnetron) and according to your website it is also a 5 year warranty on the magnetron. The consultant also confirmed that through the serial number they can track that this specific model was manufactured in November 2010 which indicates that it is still not 5 years old. I do not know who to contact or where to go anymore. How do you assist clients that receive gifts that don't have proof of purchase? Is my microwave's serial number not enough proof to indicate the age of the microwave? Your customer email support is not of much help either.