I have a message from free gold section told me “no offer available “ and I asked some friends they don’t have the same issue, is that a bug or what?

Hi guys, Really I don't know what the heck!! I have the last upgrade of rocket in training camp lvl 17, and I saw some players has the same lvl or less, but when they attacked they could destroy my rocket launcher in 1 or 2 hits, although my rocket launcher is lvl 7, but I can't do the same, I...