observeAndTransform not working Android API 25 and below

I was working with one to many reference content model where I get response like this
“name”: {},
“meta”: {},
“items”: [
I have a list in which I am getting multiple types and in repeat as well
I have created a super class of type list which is extended by all the items. I am able to parse use observeAndTransform in Android API >25 but somehow its not working below that. The data set is same.

In 25 and below I am getting CDAEntry instead of my Custom POJO

Any update on this? I guess many of us are facing similar issues