Agenda doesn’t recognise contacts

What I did:
I put in an appointment linked to my Callander and add and invitee and it says ‘no reponse’ For any and all contacts.
What happened:
It doesn’t recognise the email addresses and doesn’t sent invitations.
What I expected:
It to work. As it’s one of the reasons I bought it.

I assume this is on iOS correct? The UI for creating events is provided by Apple and not something we created I’m afraid so hard to understand what exactly this is causing. Perhaps one thing that might be going on is that Agenda doesn’t have permission to access your contacts? Did you perhaps not give it these permissions when it asked? Can you try going to the Settings app -> Privacy -> Contacts and check whether Agenda has the permission to access your Contacts?