The Resolved date and Resolved By fields are automatically populated by the system when the Issue or Risk Status is set to Resolved.
Only when the Status has been updated to Resolved is when those fields are populated.
If the Risk or Issue Status has been set to Closed and this was never set to Resolved previously, the fields will be blank.
Logical flow for Issues and Risks Statuses: Open > Work In Progress > Resolved > Closed
The Resolved Status is the key for the Resolved Date and Resolved By fields to be populated.