Daniel was a chakham gadol.
And "Chakham 'adif mi'navi/ A chakham is better than a navi."
In other words a navi has a vision what will be but the chakham knows what will be.
Thus Daniel's writings are not prophecy but wisdom, which is greater.
ב. דַּע, לְפִי גּדֶל יְדִיעַת הַתּוֹרָה וְטִבְעֵי הָעוֹלָם כֵּן נִמְסַר וְנִשְׁתַּעְבֵּד ...
There have been various rabbinic interpretations on this issue. In addition to Tamir's note on Rashi's commentary (to Megillah 3a) - that Daniel was not technically considered a prophet since he didn't publicly declare his visions to the Jewish people - here are a few other explanations.
The Rambam offers an intermediate position - arguing that Daniel had a &...