Chainsaw Repair

Any ideas on why this 026pro wont idle down when not cutting wood. Was told by 3 different shops that it be sitting and not being used. They said to use it for awhile to see what happens. I used it for few times since then. I can get it idle down at times to a point where it almost acts as if its going cut off on idle. Chain moves on idle also but when it idles down where acts as if gonna cut off the chain will stop. Is something I need to be concerned about as far as ruining the saw?

New fuel line, carb kit, tank vent, tank vent filter, and fuel filter.