hie. Can I correct you on how to ask the question first. (What's mean is) is not the correct way, try saying What does "not going to land" mean? or What's the meaning of "not going to land"?

I would love to practice conversation in English with you. I would love to share an interesting topic of conversation from life

This is an expression we would say something ie something won't land well , won't be taken well or sit well we are saying that it will not be received well by people ie people will not be open to it, it will not receive a good result, might be taken the wrong well, overall not a favorable outcome.