Two rooms on east side of house consistently hotter in summer/colder in winter than rest of the house…why?

On the second floor of my two-story home, the two bedrooms that are on the east side of the house are both consistently warmer in the summer and colder in the winter than the rest of the house. One of those bedrooms, on the north east corner is used as a guest bedroom. The other bedroom on the south east corner is my daughter’s room. I had an additional vent installed in that room to help control the temperature better. It’s a little better, but still not great. We had new blown in insulation added a couple of years ago, but those two rooms are still hotter/colder.
Who can I get to look at it to tell me why those her rooms are hotter/colder?