"Everyone makes mistakes at some point, so don't panic if it happens," Liz Wessel, co-founder and CEO of WayUp, tells CNBC Make It.
In fact, "Any good manager recognizes interns aren't as experienced as full-time employees, and are consequently more likely to make mistakes," says Sean Leslie, senior content strategist at Payscale.
Once you become aware of the problem, "Let your manager know as soon as possible, and come with a solution to the problem," says Wessel. "No one wants to hear about a problem without also hearing some sort of solution."
Wessel also stresses the importance of not repeating your errors. "Make sure you understand your mistake and that you learn from it," she says.
And once you've done all that, "Don't let it affect the rest of your work," advises ZipRecruiter CEO Ian Siegel. Obsessing will only cause you to make more mistakes.
I followed the experts' advice and, luckily, my supervisor had her badge returned with just a stern warning.
As for the I-9 documents, I discovered the following day that the office I was searching for was at CNBC's headquarters in New Jersey, not at Make It's office in Manhattan, where I was.
That's another lesson: Always ask lots of questions.
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