This has been happening every since I selected the Shake Shack Burger a few weeks back on BOS-MCO flight. Now when I try to select my entree I get "Entree Failed To Save - We are unable to save your request right now: Please try again later." This is the third time now and my wife is traveling with me has the same issue in the app. Also , my daughter who's on her own reservation not linked to ours and she purchased the ticket not a complementary upgrade has the same issue. Is this a known bug at this point ? The first time it happened I chatted with an agent and they were able to set it correctly after trying to figure out how to do it in a 20 min chat.