Code to check if field already contains data ...???

See if this helps

Public Sub InOut_Header()

Dim Lastrow As Long
Lastrow = Cells(Rows.Count, 1).End(xlUp).Row

With Sheets("surveySheet")
    If .Range("A1") = vbNullString Then
    
        .Range("A1").Resize(1, 4).Value = Array("Registration", _
                                                "Time", _
                                                "Class", _
                                                "Type")
    Else
        .Range("A" & Lastrow + 1).Activate
    End If
        
End With

End Sub

Thanks