When using a macOS client, sometimes the mouse pointer on the remote desktop acts as if clicks occur in a position different than the one where the pointer is displayed. The mismatching position between client and server side cursors is confirmed by enabling the Input menu option showing the remote cursor.

Changing the focus to another window and then going back to the NoMachine window usually resets the pointer position.

The following TR might be about the same issue, but the workaround is different and not confirmed:
https:/kb.nomachine.com/TR01V11076