Verizon BOGO phone vs. existing Droid Eris phone
All lines that take advantage of BOGO (Buy One, Get One) Offer must be a new activation or eligible for upgrade.
Did your wife use her upgrade in January? In order for you to take advantage of a BOGO offer, both lines must have an upgrade available. However, there is always the option to add a new line and then you can take advantage of the BOGO offer.