Why don't I receive my third invoice from FRontier yet ? and I think the due date is near .Try to call the Number showing on my 2nd bill, it's impossible to reach a "real" person to help .

Good afternoon, Nghiem. My team is happy to look into this for you and verify the arrival of your most recent invoice. Please reach out to us at your convenience so that we may assist you with this. We can be contacted at anytime, 24/7, via Facebook messenger (http://m.me/frontiercorp) or by way of direct message on our Twitter profile (https://twitter.com/askfrontier). Please reference case #226853 upon reaching out and thank you in advance for your time. ~Eva

You would need to call & speak with a billing agent.