Please help to not redirect

Please try using just the shortcode [loginform] with no redirect parameter, that should redirect to the current page.

Well, that was the first thing to try, but I get redirected to the post where this place the shortcode [loginform].
If you enter any product from this list https://www.proyectoswebtilia.info/pedrasa/carta-online/ and tries to buy as a test, without the logged rather than show you the message that the product was added to the cart, rises a “modal popup box” and within the form.
The plugin that makes it possible to “modal popup box” is “SB Modal”. Here a capture so that they better understand what I mean https://snap.ashampoo.com/uploads/2015-10-17/SATXTz3R.png
After using the form within the popup, you are logged in as is expected, but i am redirected to https://www.proyectoswebtilia.info/pedrasa/blog/sb_modals/iniciar-sesion-productos/
I am looking for it not redirect to any place, if not as biting in the same product woocommerce to then make possible the purchase.
I hope you can help me
Greeting