Write Textbox Value To Range1 Cells Based On Value Of Range2 Cells?

I have the following code

VB:
For Each cell In Range("D8:D11")
If cell.Value <= Range("M2").Value Then
Cells(cell.Row, 13).Value = Me.TextBox1.Value

[Code].....

The code works to where if D8 > M2, then a cell in N2:EK2 is populated with the textbox value if D8 = a column in N2:EK2 Unlike above, the textbox value for each cell in range D8:D11 is written seperately to it's appropriate row BUT to following occurs: If row 8 user input: textbox1.value = "name1", then the appropriate cell in row 8 will contain "name1" But if row 9 user input: text1.value = "name2", the appropriate cell in row 9 will contain "name2" AND the "name1" in row 8 will change to "name2" How do recognize these as separate entities without having to create a new userform/textbox for each case?