Uniform multiple Mails

I have a problem sending multiple mails over uniform at the same time. Both emailAction work for themselves. But if I want to use both, then only html-newsletter-mail will be sent, no matter which order.

			$form->emailAction([
				'to'      => 'debug@...de',
				'from'    => $from,
				'subject' => '[' . $site->title() . '] Bierclub-Anmeldung',
				'service' => 'html-mail',
				'snippet' => 'forms/email-template'
			]);

			$form->emailAction([
				'to'      => $form->data('email'),
				'from'    => $from,
				'subject' => '[' . $site->title() . '] Newsletter Anmeldung',
				'service' => 'html-newsletter-mail',
				'snippet' => 'ka-newsletter-email',
			]);
email::$services['html-mail'] = function ($email) {
	$headers = array(
		'From: ' . $email->from,
		'Reply-To: ' . $email->replyTo,
		'Return-Path: ' . $email->replyTo,
		'Bcc: debug@.....de',
		'Message-ID: <' . time() . '-' . $email->from . '>',
		'X-Mailer: PHP v' . phpversion(),
		'Content-Type: text/html; charset=utf-8',
		'Content-Transfer-Encoding: 8bit',
	);

	if (!empty($email->options['cc'])) {
		$headers[] = 'CC: ' . $email->options['cc'];
	}

	ini_set('sendmail_from', $email->from);
	$send = mail($email->to, str::utf8($email->subject), str::utf8($email->body), implode(PHP_EOL, $headers));
	ini_restore('sendmail_from');
	if (!$send) {
		throw new Error('The email could not be sent');
	}
};
email::$services['html-newsletter-mail'] = function ($email) {

	$to = c::get('ka.newsletter.mail.to', false);
	$from = c::get('ka.newsletter.mail.from', false);
	$key = c::get('ka.newsletter.crypt.key', false);

	if ($to !== false && $from !== false && $key !== false) {

		$bcc = c::get('ka.newsletter.mail.bcc', false);

		$headers = array(
			'From: ' . $email->from,
			'Reply-To: ' . $to,
			'Message-ID: <' . time() . '-' . $email->from . '>',
			'X-Mailer: PHP v' . phpversion(),
			// changed:
			'Content-Type: text/html; charset=utf-8',
			'Content-Transfer-Encoding: 8bit',
		);

		if ($bcc !== false) {
			$headers[] = 'Bcc: ' . $bcc;
		}

		ini_set('sendmail_from', $email->from);
		$send = mail($email->to, str::utf8($email->subject), str::utf8($email->body), implode(PHP_EOL, $headers));
		ini_restore('sendmail_from');
		if (!$send) {
			throw new Error('The email could not be sent');
		}
	}
};

@mzur, could you help out with this, please?

Does it work if you use html-newsletter-mail for both? Or if you comment out the snippet and let Uniform do its default thing?