I need help activating a alltel/verizon phone?

[tysha30]

I was told by a verizon salesperson that I could purchase a Alltel pre paid phone off of eBay and be able to use it under the Alltel pre paid plan, but once it arrived I can activate it just not as a Alltel pre paid but as a Verizon pre paid. I don't want that. I already have 2 phones with Alltel pre paid. I would like to know if it is possible to activate the new phone under one of my already activated Alltel pre paid accounts and if it is how can I do it? Thanks so much.