Formatting Time and Null Time

Hi cdizzle22 

You can replace null with the current datetime with the following code. Replace "previous step name" with your last step name in Power Query Editor. 

= Table.ReplaceValue(#"previous step name",null,DateTime.LocalNow(),Replacer.ReplaceValue,{"Resolved Time"})

Then create a custom column with [Resolved Time] - [Open Time] to get the duration. 

Add another custom column to format the Duration values. The new Duration column will be Text type. 

= Table.AddColumn(#"Added Custom", "Duration new", each Text.From(Duration.Days([Duration])) & "Days," & Text.From(Duration.Hours([Duration])) & "Hours," & Text.From(Duration.Minutes([Duration])) & "Minutes")

If you want to convert format with DAX method at report side, you can refer to the following blogs:

Converting Decimal Time to Days, Hours, Minutes, Seconds in Power BI • My Online Training Hub

Calculate Duration in Days Hours Minutes and Seconds Dynamically in Power BI using DAX - RADACAD

Best Regards,
Community Support Team _ Jing
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