Incorrect syntax error near 'email' - sql

Question

I'm running Visual studio and whenever I run my application it says "Incorrect syntax error near '(the email i enter appears here)'". I hope you can spot the mistake.
Within SQL server, my email column is called 'email'
Within Visual studio, the name of the input field for my email is called 'textEmail'
Public Sub AddCustomer(Firstname As String, Surname As String, Contactnum As String, Email As String)
Try
Dim strInsert As String = "INSERT INTO customers (firstname, surname, contactnum, email) " & _
"VALUES (" & _
"'" & Firstname & "'," & _
"'" & Surname & "'," & _
"'" & Contactnum & "'," & _
"'" & Email & "'"
MsgBox(strInsert)
SQLCon.Open()
SQLcmd = New SqlCommand(strInsert, SQLCon)
SQLcmd.ExecuteNonQuery()
SQLCon.Close()
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
End Class
Code within form:
Private Sub cmdSave_Click(sender As Object, e As EventArgs) Handles cmdSave.Click
'QUERY FOR CUSTOMER
SQL.RunQuery("SELECT * FROM customers WHERE customers.email = '" & txtEmail.Text & "' ")
If SQL.SQLDS.Tables(0).Rows.Count > 0 Then
MsgBox("This Email alredy exists!")
Exit Sub
Else
CreateCustomer()
End If
End Sub
Public Sub CreateCustomer()
' ADD CUSTOMER TO DATABASE
SQL.AddCustomer(txtFirst.Text, txtSur.Text, txtNum.Text, txtEmail.Text)
End Sub
End Class
Thanks for your time.

Answer 1

You are missing closing bracket
Dim strInsert As String = "INSERT INTO customers (firstname, surname, contactnum, email) " & _
"VALUES (" & _
"'" & Firstname & "'," & _
"'" & Surname & "'," & _
"'" & Contactnum & "'," & _
"'" & Email & "')"