My female friend hasn't responded in 2 days, what should I do?

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To be clear, I first met her on a website like 7 months ago. So she's just an online friend right now, but we used to talk almost every day and now it almost always takes her a day or 2 to respond (she claims to be busy these days)
My female friend hasn't responded in 2 days, what should I do?
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