If a customer would like to access one of their licenses to work on and they do not see it in their keychain, you will need to create a login for them given they already have an active hosting subscription for at least one other license.  

1) In IDB, navigate to the customer's account.

2) Click on "Licenses."

3) Right-click and select "Edit License" from the menu.

4) Click "Users."

5) Right-click and select "Create Main Login."

6) Click the ellipsis to the right of "Customer."

7) Put in the site key and click "Search."

8) Select the customer from the list. Click "Select."

9) Click the gray back arrow in the builder to save your changes and exit the screen.