Chainsaw Repair

Scored cilinder om my dolmar and Makita Romania refused waranty because the mixture  gas and oil was not corect they said to me today!
I use 20 ml  dolmar oil for 1 L gasoline!
Loks like magnus and sawtoll was right about the carb settings Makita Romania said they are ok again?
I have send an email to Dolmar Germany to see what shoul they say about the waranty!
I have a friend with the same problem with a sthill 231 and Stihl Romania sain the same things and I am sure that he respects properly the mixture oil and gas!
Is this hapening just in Romania?
My first chainsaw a chinese saw lasted 3 years and I was cutting with her 20 m3 of wood per year!