draw a blank

(idiomatic) To be unable to produce a required piece of information.

Example:   I should know that person's name, but I'm drawing a blank.
To fail; to produce no successful response.
1856, Lucius Manlius Sargent, Dealings with the Dead (volume 2, page 472)
  "Oh," she replied, "when I came to think of it, I saw, that you were right. I thought, 'twas quite likely it [the lottery ticket] would draw a blank. […]