When a customer contacts you and has specific questions about her account status you can look it up in the Magine Pro Console.
When searching for a user in the console you can use the following customer information:
In App purchase token
For the more advanced searches, you can combine the attributes to search between by e.g.
Select the country in the dropdown to the right
In the search field type DE AND tags:VIP
Now the results will be for users with country DE and the VIP tag
It takes a while until a new user account is indexed in the search. A newly created user account will turn up in the search after 20 min.