When you create contacts (persons or companies) in your Address book, they must be always based on specific contact list.
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The contact lists help you to organize related contacts into groups.
The contact lists can be seen in the left panel.
By default, Address book includes standard predefined contact lists. However, you are not limited in creating custom contact lists up to your needs.
To create a new person:
Navigate to the specific contact list.
Click New person on the ribbon bar.
Fill in all required fields.
When done, Save your changes.