Lost saved comment list

I have been working on a pdf on document cloud by adding texts and sticky notes, highlighting and free hand use with frequent saving within the text itself and whenever i close the document it saves changes automatically. Suddenly despite the document being openned and all changes being saved, two days work in the comment list disappeared. I was wondering if i could recover it as this work is very important? Also if you keep cache files Since this document is a document cloud one not a saved copy on my android. I would appreciate any help.