Refrigerator runs continuosly, freezer side is very cold & fridge side is 28 F

Our side by side kitchen aid has been running continuously. The freezer side is very cold and there is a bit of frost on the ice and the packages in the freezer. The difusser in the fridge side also has a bit of frost showing up. I have set the controls to there warmest setting and no change is observed. Fridge continues to run 24/7. I have cleaned the condensor coils under fridge too. The compressor and refrigerant must be working well cause it is plenty cold. I think fridge needs to cycle on and off of course which leads me to think it might be a thermostat issue. Anyone have any history or knowledge based information on what might be the issue? Thanks!