Observation checklists - reassigning to another obsrver

Summary:

If a manager is assigned an observation checklist to compelte, but is off sick, we would expect to be able to reassign to another user by BPM worklist. While it appears we can do this, an error is generated.

Content (required):

When reassigning observation checklist to another manager to complete, it states that they are not a valid observer. Any ideas on how to rectify?

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