How to remove duplicates from 2 columns using Power Query

Hello Anonymous  - selecting both columns and selecting remove duplicates will produce the expected result shown in your screenshots. 

I see your comment below the screenshots about it not working on a larger dataset.  Power Query is a case sensitive language that does not automatically omit whitespace and non-printable characters.  If you have some records that appear to be the same but were not eliminated as duplicates then it is likely that they truly are not duplicates because they include some other differences that you cannot see. 

In this example below, I have two cells that appear to be the same.  However, you can see that I have removed duplicates and still see both. This is because the first cell has a space at the end that you cannot see so the cells actually are different.

Here, I have added another column to convert the characters to their character numbers which will expose those you cannot see.  Now you can see that the first cell has an extra value at the end.

In your data the Account column appears to be formatted as a number so there shouldn't be any additional characters hiding in it.  The CRM column, however, is text and could have additional characters.  You can add the column to see if there are any extra characters that need to be removed.  You could go ahead and trim and clean the column and that may solve the problem, but it also might not because that doesn't always catch everything, like if there are repeating spaces at the end.  Adding the column to check which characters are actually present is usually a good idea.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45Wcnd0cjY0MlZQitWBc5RiYwE=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}}),
    #"Removed Duplicates" = Table.Distinct(#"Changed Type"),
    #"Added Custom" = Table.AddColumn(#"Removed Duplicates", "Custom", each Text.Combine ( List.Transform ( Text.ToList ( [Column1] ), each Number.ToText ( Character.ToNumber (_) ) ), "," ) )
in
    #"Added Custom"