I am definitely not the only one having issue, but is there a way for them to test my account? It definitely does not work and has not in several months. May be an issue they are unaware of. I had logged a support incident a while back, this is what they said:
We have received reports from other players regarding this issue regarding Challenges and Invites and are still investigating this situation for a resolution. We greatly appreciate your understanding and if you have any other questions or concerns, please don't hesitate to contact us and we will be glad to help.
In the meantime, we suggest that you clear your browser cookies and cache to see if that resolves the issue. Many of our players have found that this has helped with this situation.
I did the suggested activities, even reset my email and the option to send challenges. Nothing has worked.
Thanks,