Arrived at the home due to the same issue of having a cold spot in the master bedroom after installing insulation. Customer stated that the insulation has helped but when it gets cold outside the room isn’t retaining heat. I started looking at possible issues that could still be causing the cold spots. Noticed that the windows in the master were very old and could feel air draft coming from windows. Also I’m thinking the insulation on the exterior walls of the home might have settled. Customer is having OG&E come out to do so,s sealing of windows and other things as well. Customer is going to request that they do thermal imaging done to see where the heat is being lost. Nothing on the heating and air side is wrong. It is working properly at this time.