Assistant utilizing file content but annotations object is empty

I was trying out retrieval tool in assistant.
The weird issue I have been facing is that I am pretty sure that the assistant is utilizing files while generating message but the annotations is empty.

I tried out with a few examples, in some of the cases I was getting an annotation while in most of the cases annotations were empty (I already verified through the response that the file was getting utilized)

I am facing the very same issue. File annotations are not display in my assistant in the playground.