OZMail texts happen when you upgrade from a basic phone (where you used ozmail to get your email) to a smart phone. You should be able to reply to the txt "STOP" and it should stop the texts. This worked for my wife when she got her new smart phone. Just be sure you do not have any signature or anything else besides the word STOP (all caps, not sure if that matters).
Also, if you still have your old phone, you can follow these instriuctions for the texts to stop.
OZMAIL TEXT MESSAGE - Verizon Wireless Community
Here is more reading: How to Stop annoying ozmail zmail text messages from 11-801-222-2269 - Verizon Wireless Community