Freezer too cold frosty, and refrigerator section... (by 2 users)

This problem occurred four times and unit was replaced by Kitchenaid and problem remains after four years.. the freezer section is extremely cold, so cold it freezes up the air vents solid and blocks cool air the refrigerator section causing it to be warm.. had four visits by repairmen.. none have fixed it.. should I just junk it and replace with a non kitchenaid brand?