"Hi, I emailed you before but you must be busy. So this is super easy. All you have to do is email me back one number.

1. You are super busy and forgot to email me back
2. You were abducted by aliens
3. You already purchased what i'm selling"

Anyway, I don't know who comes up with these new formats of business spam. They are so annoying and useless. They'd be way better off to write sincere emails one by one instead of just spamming everyone. But I guess it works for some people or they'd naturally stop.