Adding a new row of data after the last - excel

Question

I have a list of data on my Excel file. I want to add new elements to this list by using a userform.
The code below should add the data on column B, one after the data on the last row.
The problem is each time I add a new data, my code deletes the old data.
So if I have data on column B line 3, it deletes what is in line 3 (the last row) and adds what I've just entered in that line.
Private Sub CommandButton1_Click()
Dim ws_liste As Worksheet
Dim fin_liste As Integer
Set ws_liste = ActiveWorkbook.Worksheets("Liste_Lame_" & Me.ComboBox_Modele.Value)
fin_liste = ws_liste.Range("A" & Rows.Column).End(xlUp).Row
'fin_liste = ws_liste.Range("A65533").End(xlUp).Row
ws_liste.Cells(fin_liste + 1, 2) = Me.ComboBox_Num.Value & "-" & Me.TextBox_Mois.Value & "-" & Me.TextBox_Annee.Value & "-" & Me.ComboBox_Modele.Value & "-" & Me.ComboBox_Const.Value
Unload Me
End Sub

Answer 1

I don't understand why you use this code
fin_liste = ws_liste.Range("A" & Rows.Column).End(xlUp).Row
It always give you value "1" and never change, that's why the new data will delete the old one.
I'll give you two solutions, choose what you want.
First, take one cell to save a value from fin_liste as integer (for example I choose cell "D1"). Then add "i" for a new variable as integer.
Here the code.
Private Sub CommandButton1_Click()
Dim ws_liste As Worksheet
Dim fin_liste, i As Integer
Set ws_liste = ActiveWorkbook.Worksheets("Liste_Lame_" & Me.ComboBox_Modele.Value)
fin_liste = ws_liste.Range("A" & Rows.Column).End(xlUp).Row
i = Range("D1").Value + fin_liste
'fin_liste = ws_liste.Range("A65533").End(xlUp).Row
ws_liste.Cells(i + 1, 2) = Me.ComboBox_Num.Value & "-" & Me.TextBox_Mois.Value & "-" & Me.TextBox_Annee.Value & "-" & Me.ComboBox_Modele.Value & "-" & Me.ComboBox_Const.Value
Range("D1").Value = i
Unload Me
End Sub
But there's a risk, if value in "D1" has changed, it make your data in a mess.
Second option.
Private Sub CommandButton1_Click()
Dim fin_liste As Range
Set fin_liste = ThisWorkbook.Worksheets("Liste_Lame_" & Me.ComboBox_Modele.Value).Cells(Rows.Count, "B").End(xlUp).Offset(1, 0)
'fin_liste = ws_liste.Range("A65533").End(xlUp).Row
fin_liste = Me.ComboBox_Num.Value & "-" & Me.TextBox_Mois.Value & "-" & Me.TextBox_Annee.Value & "-" & Me.ComboBox_Modele.Value & "-" & Me.ComboBox_Const.Value
Unload Me
End Sub

Answer 2

ws_liste.Range("A" & Rows.Column).End(xlUp).Row will evaluate to the first row in the range due to the xlUp parameter.
Since you are adding one to the row index in the following line (ws_liste.Cells(fin_liste + 1, 2)), I am assuming you are trying to refer to the last row of the range. You can achieve this by using xlDown instead of xlUp.
fin_liste = ws_liste.Range("A1").End(xlDown).Row
Edit: As SJR noted, If there is no data in column A, using xlDown on A1 will not find the last row of the data, but instead the next non-blank cell in column A. Instead using xlDown on the column that contains the last row of data would be correct.