Forms :: Write Conflict Message Box Appears?

I have a form for updating contact details of customers/suppliers. Upon clicking an edit button the user can update txt boxes (as opposed to updating the table data directly and making a mistake). When they press save the below code runs:

Code:
If Not IsNull(Me.txtp_fname.Value) Then
Dim strFirstName As String
strFirstName = Me.txtp_fname
Dim FirstName As String
FirstName = Replace(strFirstName, "'", "''")
End If

[code]....