I believe I understand your problem: "now" logically refers to the present (or the very near future) and "never" to some point between present and more or less remote future. One could say "Your son will not come now" or "Your son will never come" but "Your son will never come now" sounds awkward to me, too.
On my screen ayega option is not visible. It appears as ayaga (the top mark on ya). I am seeing this problem for others also recently (missing top marks). Does anyone have this problem. I did reported this issue, but I didn't get any answer. This has been happening since I think recent windows update on surface tablets.