It's possible the question has already been asked here, but wasn't able to find. So please excuse me for posting this again.
The early Jewish philosophers/thinkers (Saadia, Ramabam, Bachya Ibn Pakuda in Shaar hayichud) stressed the absolute unity of God, i.e., that Hashem is absolutely one, a unified entity with no distinct parts or attributes. As we say in the Ani Maamin הוּא יָחִיד וְאֵין יְחִידוּת כָּמוֹהוּ בְּשׁוּם פָּנִים
The sefirot, the divine emanations, which are also in some way identified with the Godhead (Shechina for example is distinct from the ein sof, but paradoxically also identified with it), stand in direct contrast to the absolute unity of God. Some (see teshuvas Rivush 156) even went so far to compare this to the Christian concept of trinity.
My question is how did the early kabbalists (like the Ramban and Rashba, who were also philosophers and great thinkers) reconcile this belief with the belief in the absolute unity of God? Did they disagree with the concept that God must be an absolute single entity, or did they reconcile this in some other way?