I came through an invite link, but my invite code doesn't show at sign-up
The invite code only comes with the invite link and appears at the top of the sign-up form; the form has no field for typing the code manually.
The invite link opens the sign-up page together with the code. The “Invite code” row at the top of the form shows your code and the offer made to you: a 7-day free trial, then 30% off the first 3 paid months.
If the row doesn't appear, the link may have been copied incompletely. The form has no field for typing the code manually; ask the person who invited you for the link again.
If you don't want to use the code, press the “Remove” button; if you change your mind, you can bring it back with “Undo”. If the code is removed, the discount isn't applied.
The company that invited you can see that you signed up and whether the invite counted. The invite only applies to a newly created account; it doesn't count for accounts created from the same company domain as the inviter.