Replacing values with Previous Non-error Value

I have here a sample table that has 2 columns: Timestamp & Demand. Unfortunately, some of the values of demand columns has a value of -3276.8 as shown below due to error in data collecting. However, I want to correct this by replacing this value to the latest preceeding value that is not -3276.8. I want this column to be added in power bi query editor. Need assistance on this. Thanks>

Current View in Power BI Query Editor.

Expected Result: