I was recently charged , which was higher than normal. Today I investigated this by looking to see how many email addresses we were up to. WHOA, well over 500. Turns out over 120 of them were fake! Yes, there were troll-level fake email addresses, but I mean robot generated fake emails with names like; "5k6hth8hyd8d9s" The majority of the 120+ were these types of emails.
Something doesn't seem right about it, and I've paid for it.
Thank you for reaching out to the Community! It sounds like you may have a sign-up form on your website that was affected by a bot attack. That means you were spammed with fake email addresses. If you have a sign-up form on your website, that is not one of ours, I suggest using one that you create on your account. It adds protection from bot attacks after a certain amount of email addresses signs up on it. I recommend deleting those email addresses out of your account, and letting us know if these could have came from a sign-up form.
Thank you for giving us this update. Because you are using one of our sign-up forms, I would suggest enabling the confirmed opt-in for new sign-ups. This setting will send an automatic confirmation email when contacts join a a list. This confirmation email not only helps to ensure your permission to send, but also to weed out any spam emails as well.