Donald Trump signed a pledge Thursday promising not to run as an independent in 2016, announcing the move at a well-attended press conference at Trump Tower. 

There was just one problem. The copy of the pledge that Trump held up, signed in thick black ink, had the wrong date.

Though Trump signed the pledge on Sept. 3, the document appeared to show the date, “August 3/15.” 

When asked about the mistake, the GOP's 2016 presidential front-runner dismissed it as someone else’s error.

“They put it in … yeah. Somebody else wrote it. We’ll change the date,” Trump said.

The candidate later tweeted a corrected document. 

The pledge states in part that if the GOP contender does not become the nominee: "I will endorse the 2016 Republican presidential nominee regardless of who it is," and "I will not seek to run as an independent or write-in candidate nor will I seek or accept the nomination for president of any other party."

After Trump tweeted, GOP rival Jeb Bush tweeted his own pledge, of sorts.