I have created a promotional pop up for subcriber, but the subscribers only show in google drive and not in squarespace email subscriber

What am I doing wrong? I have chosen storage in SQUARESPACE EMAIL CAMPAIGNS and Googe drove. 

I have this issue also. Did it ever get resolved?

I've just ran a test and the mailing list storage and Google Sheets appear to be working.

One thing that might confuse you is when you go the email route, the recipient has to confirm via their email address that they indeed want to subscribe before their name will show up on the mailing list.