Why am I getting an error sending competition invitations on the Fitness app on my Apple Watch?

My wife and I are both paired on our phones and apple watches. When trying to compete on the fitness app using our apple watches the link goes out but we get the error: Error sending your competition invitation to XXXXXXX. Please Try Again. My wife went to the apple store here in Tampa and they couldn't figure it out. We've deleted and added each other as contacts and not getting anywhere. Could use some help...

[Re-Titled by Moderator]