I got the code for a free birthday E+, but the code does not work for me. (It's the generic promo code....I figure it's just validating against my actual birthday in my account.) Tried it on two of my September flights with nearly empty E+ cabins. Does not work in either app or website.

Maybe I'm doing it wrong, but it's a pretty useless promo if it isn't easy to use. I'm Silver and will almost certainly end up in E+ on these off-peak flights anyway so not losing too much sleep over it. Just frustrated by the poor execution of a nice idea.