Fillable fields have disappeared

Hi 

Im hoping someone might be able to please help me with Acrobat DC Pro

Yesterday I created a large document with numerous fillable fields throughout the document. All was working fine and I could populate each of the blue fields on the document.

This is where things go wrong - I then tried to add a signature which i struggled with but also tried to delete that and during this time i think the dcocument saved.

Now when I open the document I can no longer see the fillable fields and can only see them when i click on the 'prepare form' tab, then when i close this they all disappear again almost as if the document is locked and I am unable to do anything with it.

Anyone got an ideas as to whats happened?

Thanks