Ever come a cross clients that all of a sudden their Contact Logs have disappeared from the Enrolments & Results area.
This is a common occurrence, and is easily fixed.
The contact logs on the Enrolments and Results area has a Filter and likely this is set on a status that doesn't show logs for the client.
If changed to filter on "Both Open & Closed" all will appear.
If for any reason that you need to transfer a client from one course to another. To avoid losing any created contact logs relating to the original course, open the log and change the Contact log from a Course to Generic Contact related Log. See picture below.