By default, Kolleno imports the contact persons related to a customer (4 on the schema below). You can find more information here.
If you wish to import the contact details recorded in the fields at the customer level, you can do so by asking your Kolleno account manager to activate the option.
If you look at the schema, it will create in Kolleno a contact person with:
First name (1)
Phone number (2)
Email address (3)
Please note that (1) can be replaced by the "Attention" field of the customer's address. Please speak to your account manager to activate this.
If you wish to import email addresses saved in custom fields, and possibly automatically assign them a position, your Kolleno account manager can help with that.