If a future sub-account owner did not receive or loses your original invitation, you can easily resend one by using the process described below.
To Resend a Sub-Account Invite:
Click on your profile picture in the top-right corner. Then, click on Manage Sub-Accounts.
At the top of this page, click on the Pending Invites tab.
You should see all of the invites you've sent within this table. If you do not see the contact in question, you still need to send out the original invite. You can learn how to do this here. Otherwise, continue below.
Hover your cursor over the contact in question. Notice that a blue email icon appears next to the Owners Email column.
Simply click this icon and a new invite will be sent.
You should see a message in a green bubble in the bottom left corner of the page to confirm.
Be sure to communicate with the contact that you are sending a new invite to avoid any additional issues. If your contact is still not receiving the invite, please contact support as soon as you can to report this bug.