There's no Submit button?
That's typically where you would put cleanup and validation.
Also, if the only alphabetic character in the user ID is the first one,
you can just set Textbox1.Tex to upshift(Textbox1.Text) (in the text blocks, maybe different name)
BTW, that's an awful name for a Textbox.
You can rename it easily in the Designer, and every reference will follow.