Thanks a lot for your messgae! It's much better to know I am not the only one!

But, do you know what's the difference between the first and the second?
Will they ask me to prapare every document again or ask me the similar questions again?
What's the meaning about the second interview?

The official is impatient when I asked here why I need the second. She just told me sometimes they need it to validate.

Thanks again!