I am seeing posts from people from 6 years ago and here I am in 2021 having the same issue. Apple support should really make this process easier for users! I have also tried contacting support to request a call, which they promise will take place in less than a minute but to no avail. I have also sent a support email but lord knows if anyone is even monitoring that mailbox.

I can't believe this is still an issue in 2021, Apple should just create a button that allows you to resend an invite!!!