HELP: It's been a week and still no results from background check

I got a job offer last week, which I accepted. They said to wait until background check is back to give my current employer a notice and confirm my start date.

They also said the process could take 10 business days. It's been about five so far.

I have no criminal history that I know of, and I didn't lie about my education or employment (they verify) that.

Any reason why it could take that long? If I haven't heard back on anything by now, is that a bad sign?

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