Force Login failed

Hello

I try to add this script to my wp function.php after install and activate force login plugin

// Custom Login URL
function my_login_page( $login_url, $redirect ) {
    return site_url( '/custom-login/?redirect_to=' . $redirect );
}
add_filter( 'login_url', 'my_login_page', 10, 2 );

But it’s failed, my website is redirected to the wrong URL. I don’t know why.
It’s like this (too many redirects): https://prnt.sc/1ry8igj

Please help

thank you

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