New Post: Subject has property Subject that the other object does not have

I must be doing something wrong or missed some documentation. I have two DTO's that I am comparing and they are both the same as far as I can see in the debugger.

However when I try

resultDto[i].Should().NotBeNull().And.ShouldHave().AllProperties().EqualTo(controlDto[i]);

I keep getting this error "Subject has property Subject that the other object does not have", apparently the .AppProperties() wraps the first object. I know I'm doing something wrong here. A quick answer would be great.