How to get value of property from object of class at runtime using reflection

I have a class something like below:

Class A : B<C>
{
    public A(C entity):base(entity)
    {}
}

abstract class B<T>
{
    public B(T entity)
        {
            Entity = entity;
        }

        public T Entity { get; private set; }
}

Class C: D
{
    public string prop2{get;set;}
}
Class D
{
    public string prop1{get;set;}
}
 Main()
 {
 A obj = new A();
 obj.GetType().GetProperty("prop1",  BindingsFlag.Instance|BindingsFlag.FlatteredHierarchy)//  is null


 }

I have object of class A. I want to get property value from this object at runtime.

I am trying with

obj.GetType().GetProprty("propertyName", 
                         BindingsFlag.FlattenHierarchy).GetValue(obj, null);

However GetProprty() is returing null as that property is declared either in B or C class.

Can someone please suggest me how to achieve this?

Thanks in advance.