VB.net - TextBox updated via code is not committed with DataTable.AcceptChanges - vb.net

Question

I have what I believe to be a small oddity in my code. I have a textbox (txtEmail) that get text added to it via code: txtEmail.Text = "Text Here" If I don't tab through the text box before I try to save the record, the text is lost when executing the DataTable.AcceptChanges.
I have tested this by:
Not tabbing through the textboxes - Text gets lost
Tabbing through the textboxes- Text is committed
"Selecting" the textbox via code, then selecting another textbox - Text is commited
Is there something I am missing? Is there any way I can commit the text without selecting or tabbing through the textboxes?
For reference, the textboxes are bound to a binding source, who's DataSource is a DataTable.
Some snippets of code to maybe help...
Filling DA and DT, setting BS:
Using SQLcmd As New SqlCommand With {
.Connection = Vars.sqlConn,
.CommandText = "SELECT * FROM [Database].[Table]"}
da_Users.SelectCommand = SQLcmd
Dim sqlCB As New SqlCommandBuilder(da_Users)
AddHandler da_Users.RowUpdated, AddressOf OnRowUpdated
da_Users.Fill(dt_Users)
dt_Users.Columns("Active").DefaultValue = True
dt_Users.Columns("Phone").DefaultValue = "6-1800, ()"
bs_Users.DataSource = dt_Users
bsnav_Users.BindingSource = bs_Users
End Using
Updating Email Textbox
Private Sub txtName_Leave(sender As Object, e As EventArgs) Handles txtLastName.Leave, txtFirstName.Leave
Try
Dim tb As TextBox = DirectCast(sender, TextBox)
tb.Text = StrConv(tb.Text, VbStrConv.ProperCase)
If Not txtFirstName.Text = "" And Not txtLastName.Text = "" Then
Dim strFNames() = txtFirstName.Text.Trim.Split(New Char() {" "c})
Dim strLNames() = txtLastName.Text.Trim.Split(New Char() {" "c})
txtEmail.Text = strLNames(0) & "." & strFNames(0) & "#sample.com"
End If
Catch ex As Exception
CustExErrorMsg(Name, Reflection.MethodBase.GetCurrentMethod().Name, GetExceptionInfo(ex))
End Try
End Sub
Saving the record:
Private Sub btnSave_Click(sender As Object, e As EventArgs) Handles BNavSaveItem.Click
Try
If IsComplete() Then
If blnNew Then If IsDuplicate() Then Exit Sub
lblTSS.Text = "Saving..."
lblTSS.BackColor = Color.IndianRed
Application.DoEvents()
'Added to commit text
txtEmail.Select()
txtFirstName.Select()
Me.Validate()
If blnNew Then dt_Users.AcceptChanges()
bs_Users.EndEdit()
da_Users.Update(dt_Users)
lblTSS.Text = "Done"
lblTSS.BackColor = Color.LightGreen
End If
Catch SqlExceptionErr As SqlException
CustSQLErrorMsg(Name, System.Reflection.MethodBase.GetCurrentMethod().Name, SqlExceptionErr.Message)
Catch ex As Exception
CustExErrorMsg(Name, Reflection.MethodBase.GetCurrentMethod().Name, GetExceptionInfo(ex))
End Try
End Sub