Replace values to null in matrix table

sagar512 Sorry, having trouble following, can you post sample data as text and expected output?
Not really enough information to go on, please first check if your issue is a common issue listed here: https://community.powerbi.com/t5/Community-Blog/Before-You-Post-Read-This/ba-p/1116882

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The most important parts are:
1. Sample data as text, use the table tool in the editing bar
2. Expected output from sample data
3. Explanation in words of how to get from 1. to 2.

Hi sagar512 

Thanks for reaching out to us.

please try this, go to Power Query Editor, and select all columns then select replace values,

result

FYI: 

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WCg70UdIBk7E6MF5oXnZefnkeWATGRlcD5sUCAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}, {"Column2", type text}}),
    #"Replaced Value" = Table.ReplaceValue(#"Changed Type","Unknown",null,Replacer.ReplaceValue,{"Column1", "Column2"})
in
    #"Replaced Value"

Best Regards,

Community Support Team _Tang

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