Hi, thanks for your kind help. I am married and my husband lives in China, and it is not possible for him to apply the SSN, and how to solve it.

I am a resident alien, and my husband lives in China,  so in the personal info, I wrote the married status and I selected the file jointly, and the system reminded me that I must fill my husband' SSN in the Form, and I do not know how to solve it.  I very appreciate your kind help.