The creator created creation.
The creator (the one who brought things to be) created (made to be) creation (that which has been made). To be the thing that created the act of creation, that thing must itself exist regardless of the act of creation. Since the act of creation (causing something to be) is the essence of all reason, we must then concede that that thing exists regardless of reason.
The very desire to seek the reason, the cause, the root of all things inevitably leads to the acknowledgment that there must be a point at which cause and effect itself was caused. Up until that point, an existence “was” that cannot be understood nor constrained by what “is.”
I cannot employ reason to find the Creator any more effectively than a cake can employ reverse engineering to find its baker.