I have a Visa Signature card (FYI - signature cards are for people with outstanding credit and actually allow charges over your credit limit). Credit limit is $15,000. Card has a zero balance on it.
There was absolutely zero reason for the charge to be declined. I have had this card since 2006, and have never had a charge declined on it until today. Since there are multiple people on this forum with the same experience, this tells me that Verizon has a trash e-commerce site that is written so poorly it trips fraud alerts at apparently almost every bank in the country.
This is all on Verizon - not me.
Definitely a weird situation. I also used my Visa Signature branded card and mines went through without a hitch.