Hi Lisa,
Thank you for your question!
I tested this through your event app and the + button was appearing for me. I've attached two screenshots here.
Please try logging out of the app and re-logging in. The app may need a reset to have that feature show up.
Hope that helps! If you are still experiencing issues, please give our customer care team a call and they will be able to further troubleshoot.
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Sydney Langer
CSA
Cvent
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