date data type

Anonymous Ideally, I would ensure the source is correct but you can try to add a new column in PQ or you can transform the column in place, create a new query and paste this code in the advanced editor and observe the last 2 steps

let
    Source = 
        Table.FromRows (
            Json.Document (
                Binary.Decompress (
                    Binary.FromText ( "i45WMjTSNzbUNzIwMlKK1YlWArKBIhBuLAA=", BinaryEncoding.Base64 ),
                    Compression.Deflate
                )
            ),
            let
                _t = ( ( type nullable text ) meta [ Serialized.Text = true ] )
            in
                type table [ Date = _t ]
        ),
    ChangedType = Table.TransformColumnTypes ( Source, { { "Date", type text } } ),
    AddColumn = 
        Table.AddColumn (
            ChangedType,
            "Dates Fixed",
            each 
                try Date.FromText ( [Date], "en-IN" ) 
                otherwise Date.FromText ( [Date], "en-US" ),
            type date
        ),
    TransformColumn = 
        Table.TransformColumns (
            ChangedType,
            {
                "Date",
                each 
                    try Date.FromText ( _, "en-IN" ) 
                    otherwise Date.FromText ( _, "en-US" ),
                type date
            },
            null,
            MissingField.Ignore
        )
in
    TransformColumn