You can sue for any reason whatsoever - does not mean you will win.
I am sure that Verizon was smart enough to put a limitation on the time that one had to activate the service. They have very many lawyers that would never allow a deal with no end date.
But again, you buy something over 1 year ago and only activate now? Did you really need this service?
Anyhow - you should not expect people to have a special offer that never expires, you must activate it to get the benefits.
But honestly, sounds like you are crying over nothing if it is really 1 year ago that you purchased this. You are being unreasonable.