Unable to edit a graph

[#1]

Hello, I am attempting to edit a handful of pre-made graphs (they have not been ungrouped or touched an anyway since creation) I can select work on the artboard and go to objects-graphs-data, but when the data box pops up it is completely empty? Is there a setting i have wrong somewhere that is auto ungrouping these charts?

[#2]

Hello, I am attempting to edit a handful of pre-made graphs (they have not been ungrouped or touched an anyway since creation) I can select work on the artboard and go to objects-graphs-data, but when the data box pops up it is completely empty? Is there a setting i have wrong somewhere that is auto ungrouping these charts?

[#3]

When you select the diagram and then look inside the layers panel: what does it tell you? Is the still a graph?

[#4]

I am having the same issue. Any luck on this?

[#5]

Can you upload a sample file to Dropbox or the like?