Recently we have had many failed attempts to subscribe from email addresses mostly from gmail.com. Google is telling us:
"550-5.2.1 The user you are trying to contact is receiving mail at a rate that
550-5.2.1 prevents additional messages from being delivered."If you are not receiving an email to confirm your subscription, this may be the problem.
If this is the case for you, please contact us by email so we can manually add your subscription.