You mean before or after breakfast?
If before, I just have something carby while making breakfast. A little bread & jam, a date, even a cookie.
If after, possibly not eating enough for breakfast? Possibly too much liquid in your breakfast? If it’s an hour or two after breakfast, then it’s time for “second breakfast” like a Hobbit, or at least a snack.
Is there a psychological component, as well, to contemplate? E.g., anxiety about work?