Why no flag?
Why is it that when I leveled up, there wasn't a flag connected to the number?
I am having the same issue. I just reached Level 4 and a flag is still not connected to the number on my profile...just one of the kinks of Beta I suppose :)
I don't think it's beta-related. Sometimes some parts of duo take time to notice things other parts have done. Probably some information is cached for performance reasons, and can be stale when it's used. Both your level and languagelover's are showing now.
They are talking about the activity stream. When you level up, no flag indicator is shown. That's what the OP asked about (and not those next to the user).