What "we applied $0.00 to your monthly plan" means to Verizon

This is just a brief note that will (hopefully) help someone in the future. When Verizon sends you a text message that says:

Verizon Msg: There is a credit on your account. We applied $0.00 to your monthly plan. Your card was not charged.

What it actually means is “Six months ago your credit card expired and we’re now no longer able to charge it, so we have shut off your account. There will be no further communication on this topic.”

Thanks, Verizon!