Removing duplicates, keeping information and summarizing VBA

So I am trying to handle some data through VBA and I have a hard time figuring out how to do this the correct and less time consuming way when the data is getting handled.
I have an excel sheet that contains data from A:V with dynamic rows and including headers. But there is a lot of the data I do not need for any reasons.
So, my task is to take column K, P, Q, T, U, and V, and find all the unique combinations/values from this. Then I want to take this unique value and summarize what is in Column O. Afterwards I want to print this to a new sheet, where I have printed all the columns that made the combination. It could look like this:

The idea is just to tell that there can be a lot of combinations with so many columns. But in this case line 1 and 3 could be contained in 1 row, and instead present 8 in head0.
Can anybody help me with this?

I have actually tried some code from chatgpt, but can't get it to work correctly. I know it is not allowed to answer with it, but guess this is my own post, so I can admit my own mistakes....

Sub SummarizeData()
    Dim ws As Worksheet
    Dim dataRange As Range
    Dim uniqueValues As Collection
    Dim cell As Range
    Dim uniqueValue As Variant
    Dim summaryArray() As Variant
    Dim summaryIndex As Long

    ' Define the worksheet
    Set ws = ThisWorkbook.Sheets("TimeRegistrations_Billable")

    ' Define the data range
    Set dataRange = ws.Range("K2:V" & ws.Range("K" & ws.Rows.Count).End(xlUp).Row)

    ' Create a collection to store unique values
    Set uniqueValues = New Collection

    ' Iterate over the data range
    For Each cell In dataRange.Columns(1).Cells
        uniqueValue = cell.Value & cell.Offset(0, 6).Value & cell.Offset(0, 12).Value & cell.Offset(0, 13).Value & cell.Offset(0, 14).Value
        On Error Resume Next
        uniqueValues.Add uniqueValue, uniqueValue
        On Error GoTo 0
        uniqueValues.Add cell.Value, cell.Value & cell.Offset(0, 6).Value & cell.Offset(0, 12).Value & cell.Offset(0, 13).Value & cell.Offset(0, 14).Value & "K"
        uniqueValues.Add cell.Offset(0, 10).Value, cell.Value & cell.Offset(0, 6).Value & cell.Offset(0, 12).Value & cell.Offset(0, 13).Value & cell.Offset(0, 14).Value & "T"
        uniqueValues.Add cell.Offset(0, 11).Value, cell.Value & cell.Offset(0, 6).Value & cell.Offset(0, 12).Value & cell.Offset(0, 13).Value & cell.Offset(0, 14).Value & "U"
    Next cell

    ' Create an array to store the summarized data
    ReDim summaryArray(1 To uniqueValues.Count, 1 To 5)
    summaryIndex = 0

    ' Iterate over the unique values
    For Each uniqueValue In uniqueValues
        summaryIndex = summaryIndex + 1
        summaryArray(summaryIndex, 1) = uniqueValue
        summaryArray(summaryIndex, 2) = WorksheetFunction.SumIf(dataRange.Columns(15), uniqueValue, dataRange.Columns(15))
        summaryArray(summaryIndex, 3) = uniqueValue & "K"
        summaryArray(summaryIndex, 4) = uniqueValue & "T"
        summaryArray(summaryIndex, 5) = uniqueValue & "U"
    Next uniqueValue

    ' Add the summarized data to a new worksheet
    With ThisWorkbook.Sheets.Add(After:=ThisWorkbook.Sheets(ThisWorkbook.Sheets.Count))
        .Name = "Tester"
        .Range("A1").Resize(uniqueValues.Count, 5).Value = summaryArray
    End With
End Sub

So I actually have found 1 way to do it, I just need to remove all the duplicates in column 23 though. But this takes like ages to run, when you have 500k lines.
Don't know if this code makes more sense.
But when the duplicates in data1 column 23 has been removed, I have the data I want as the end gold (and more columns included which is not needed).

Sub uniquevalues()
Dim data1 As Variant, data2 As Variant
Dim lastRowTRB As Long, lastRowdata1 As Long
Dim timer As Double
Dim i As Long, k As Long

lastRowTRB = Worksheets("TimeRegistrations_Billable").Cells(Rows.count, "A").End(xlUp).row
data1 = Worksheets("TimeRegistrations_Billable").Range("A1:X" & lastRowTRB).Value

For i = 2 To lastRowTRB
    If i > UBound(data1, 1) Then Exit For
    data1(i, 23) = data1(i, 11) & data1(i, 16) & data1(i, 17) & data1(i, 20) & data1(i, 21) & data1(i, 22)
Next i

data2 = data1

For i = 2 To lastRowTRB
    If i > UBound(data1, 1) Then Exit For
    timer = 0
    For k = 2 To lastRowTRB
        If k > UBound(data2, 1) Then Exit For
        If data2(i, 23) = data2(k, 11) & data2(k, 16) & data2(k, 17) & data2(k, 20) & data2(k, 21) & data2(k, 22) Then
            timer = timer + data1(k, 15)
        End If
    Next k
    data1(i, 24) = timer
Next i
    
    With ThisWorkbook.Sheets.Add(After:=ThisWorkbook.Sheets(ThisWorkbook.Sheets.count))
        .Name = "Tester"
        .Range("A1").Resize(lastRowTRB, 24).Value = data1
    End With