I have made this typo myself, on occasion, so I thought I would take the opportunity to offer it to you as well. Some people use mnemonics to help them remember difficult spellings, or simply to remind them of what a word itself means, or perhaps even to inspire a certain esprit de corps ("There's no I in TEAMWORK"), but that sort of thing rarely helps with a simple slip of the finger. Today's word contains both a Y and an I, and even a Y-O-U of sorts, not to mention two O's, two P's, and two T's. So you've got a lot of options here. It's just a matter of taking it slow, making sure you've dotted your I's and crossed your T's, and then not blowing the whole thing right at the very end. There were three missed opportunities in OhioLINK today, and 23 in WorldCat.
("We're ready! For the challenge of tomorrow. Let's do the job ... together!" Poster art, 1941–1945, courtesy of the National Archives and Records Administration, and Wikimedia Commons.)