Problem solved by doing a clean install of Canon Utility 3, and a full reset of the camera's settings.

Canon R7, RF 35mm f1.8 macro AF lens, Windows 11, USB connection.

All camera functions are available through Helicon Remote except for using any of the < > buttons to adjust focus. There is no response, even though the autofocus function works normally.

The same < > buttons work normally to adjust ...