Try refreshing the page.
Are you on a Team? It's possible that the property has not been added to your team yet. To discover follow these steps:
Go to Settings>Account
Select the Teams tab
Go to your team and select
Select Next on Team Details
Search for the property
If it is selected already please reach out to support
If it is not selected please select the property and click Next
Click Next again on Unit Details
When you arrive at Users click Save
You have now added the new property onto your Team.