The "Next" button will stay disabled until the operator and machine are properly selected.
Choosing the operator
To choose an existing operator, start typing their name and a dropdown menu will appear with suggestions so you can pick the desired one.
Choose an existing operator from auto-suggest dropdown
Upon selecting the operator from the dropdown, it will be highlighted in a black box with white letters as shown in the image above.
If you want to create a new operator, you can simply type in its name and press the enter/return key. This will highlight it to indicate that you have chosen those operator details.