I have a maytag side-by-side refrigerator. I noticed that in the refrigerator section the low part ( where there is an air duct opening to the freezer). However, the upper part is warm. I have tried changing the temperature control it doesn't seem to be helping.

Apparently the freezer is working fine and I can feel cold air in the bottom hal the fridge. Because of this the food on the top shelves are getting spoilt because of the higher temperature.
Please note that I am getting cold water, the freezer looks fine and the lower half of the fridge also feels cold. Is there something wrong in the valves so that the warm air is not going out. If so how do I check. The fridge is around 7 years old

Please help

Sounds like your air circulation fan is not working or at least there is no circulation taking place. Check to insure that the vents are not blocked and that there is no ice built up inside the vent or on the coil.