PDF form is missing information entered on a Windows PC
Adobe recommends:


  Mac users: don't use Preview
  
  For Macintosh system users: DO NOT use the Preview program to fill in
  the PDF form. Adobe Reader is the only program that will allow you to
  work with the form properly, and allow us to read the results once
  back on a Windows machine.


The fillable PDF forms are created with Adobe app. If opened with Preview it will completely mess-up that capability, so newer open it with Preview. Happy filling.