In order to create a second or third login for a customer you need to create a Business Central Contact first.

Go to the Business Central customer list and select the customer you want to create an additional login for.

Open the Contact Name field by clicking the three dots.

Click New to create a new contact.

Start by pressing the Tab key so a Contact No. is generated. Now the contact name can be filled in, make sure the contact type is ''Person''. This is the only contact type that can have a magento account. If the contact name and contact type are filled in change the email address to the new email address which should be used to login. In Magento it is not possible to use the same email address for more than one user. If this is done, click ''Create Magento Account''.

The additional login is now created however, it has to be released in order to be synchronized to Magento. Therefore click the interactive status field to navigate to the Magento Contact Card.

On the Magento Contact Card click check all information of your new login. If this is allright, click the Release button. 

Your new login will be added to the integration queue and is being synchronized to Magento.

When navigating to the Magento Customer by clicking the interactive status field on the Business Central Customer Card, for which you just added the additional login, we can see that a contact has been added.