I invited a friend using a referral, but it shows as ineligible.

I would appreciate it if your staff didn't point me to FAQs and pre-written articles. Assume your users are intelligent, resourceful people who have already tried everything on their end. If we are reaching out to you, it means the problem isn't on our end and can't be debugged with available resources. Don't waste valuable time and reply back-and-forth pointing to various articles and docs. Step in and address the issue -- adding the space, since you know the accounts in question --  or provide a way to get in touch!