Slate Drop Down Menu Text (SObjectPropertyEntryBox)

I am using the following Slate pattern to create a drop down editor menu where I can pick an actor in the scene. While I am able to pick the actor from the dropdown menu, the text on the dropdown menu claims it cannot find the selected object.

SNew(SObjectPropertyEntryBox)
.AllowedClass(AActor::StaticClass())
.ObjectPath(this, &SMapSnapper::GetFixedMapString)
.OnObjectChanged(this, &SMapSnapper::FixedMapOnChanged)

SMapSnapper::FixedMapOnChanged sets a member variable to the selected actor. This member variable gets set correctly even with the displayed error.
SMapSnapper::GetFixedMapString returns the aforementioned member variable’s path using GetObjectPath()

I don’t receive the error if the AllowedClass is something other than AActor, i.e., assets, materials, things that are not in the scene.