Updated

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.

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(Reuters)

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.