What was the reason for Germany's second refusal?

After the German visa was refused, the reasons given in the refusal letter were very general. To put it bluntly, they are all checked casually by visa officers and have no reference value.

But refusing to sign is not terrible. You can sign at any time after refusing, but the key depends on whether your binding force is stronger than last time. If the binding force is more than last time, you can sign it again at any time.

If you don't change anything, that is, the binding force remains the same as last time, even if you sign in 10, the result will still be rejected, so when you can sign again after being rejected has nothing to do with the time, mainly depending on whether your binding force has increased compared with last time. As long as you add it, you can sign it again right away.

In fact, it is best to analyze your own information after refusing the visa to see what are the shortcomings. Check for leaks and fill vacancies next time and try to get a visa smoothly.