I have tried several times, with a few months in between, to use my Facebook app to invite my friends to join. Every time I try, I am allowed to choose the people I want to invite, but when I try to add them I am told:
We’re sorry, an error has occurred.
We’ve been automatically notified of the problem, but if it keeps occurring, please email firstname.lastname@example.org.
Like I said, this has been happening for a while, and I would really like to invite more people.