Integrated Google Sheet does not show new fields added in the form

My integrated Google Spreadsheet does not show that I added a middle name field as well as an all caps field. how do I update this? 

When you integrate, only fields that are available in the form are automatically added on the sheet. New fields are not automatically added, and to add, you need to re-integrate the form with Google Sheet, which also means you will get a new sheet for the form. 

Unfortunately, there is no way you can use the same sheet when you re-integrate, but existing form submissions are automatically carried over to the new sheet.