Enroll Learners into the offering without adding activities

We can create course offerings without activity and system allowing to enroll the learners to no activity offering. Once the employees enrolled to offering, the system automatically marked learning record as completed.

We tried all mass actions option on completed learning record to delete/undo it etc., none of the options worked.

If the system automatically marked the learning record as completed without activity, then it should not allow the offering creation without activity.

How to correct the completed learning records?