Strange behaviour in Learning - multiple completed assignments for the same user and course

Summary:

We are consistently witnessing odd issues in Learning with the latest being learners who have completed a course having multiple, duplicate completion records on that learning item. They are not assigned by an initiative so we do not know what is causing this.

Even more bizarrely the completion date is before the assignment date on each entry.

Hoping someone has an idea of how to prevent this?

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