He's God, remember? Don't try to apply your petty rules of logic to something as illogical as the imaginings of ignorant human beings.
He is not created, He is eternal. He is the One who brought time, space, and matter into existence. Since the concept of causality deals with space, time, and matter, and since God is the one who brought space, time, and matter into existence, the concept of causality does not apply to God since it is something related to the reality of space, time, and matter. Since God is before space, time, and matter, the issue of causality does not apply to Him.