The customer has 2 or more Domino Servers with same common name.
Then, please see the scenario below:
1. Create a shortcut of Database in Notes Client
2. Right-click on the Database and Open on Designer
3. Check the Database opened on Designer and you'll see that different organization server is opened.
Note: If there are more than one servers with the same common name, you'd end up hitting the wrong server.
Current workaround would be adding hostnames together with the IP Address in the host file.
Lastly, no workaround as of the moment since this is working by design that you need to add hostnames together with the IP Address in the host file.