I came to the Prophet ﷺ regarding a debt my father owed. I knocked on the door, and he asked, "Who is it?"I replied, "It is I."He said, "It is I, it is I," as though he disliked that response.
أتيت النبي ﷺ في دين كان على أبي، فدققت الباب، فقال: من ذا فقلت: أنا، فقال: أنا أنا كأنه كرهها.
Bukhari related it in "Seeking Permission" (6250), and Muslim in "Manners" (2155), both through routes from Shubah, from Muhammad bin Munkadir, who said, I heard Jabir say, and he mentioned it. The wording is Bukhari's.