FORMATTING

Does anyone know why my story's formatting is wiped out each time I upload it? I've tried everything -  "paste", "paste text", "paste from Word Doc" - it just uploads everytime as a single block of text. I've tried editing the text here on the site, putting my paragraph breaks back in. They show OK in the editing panel, but then disappear when the story is uploaded. Desperately frustrating - I think I had this issue before but I can't remember how I "fixed" it!!!! Anything any of you can add would be greatly appreciated - on balance I'd rather not upload anything than upload that! Thanks in advance AJB