Christ is currently ruling and reigning over all things. “Everything [is currently] in subjection under his feet,” and God the Father has “left nothing outside of [Christ’s] control” (Hebrews 2:8). In other words, regardless of how many “kingdoms” there may or may not be, there is only one “King.” And this King is presently ruling over everything, even sin and suffering.
19 …According to the working of his great might 20 that he worked in Christ when he raised him from the dead and seated him at his right hand in the heavenly places, 21 far above all rule and authority and power and dominion, and above every name that is named, not only in this age but also in the one to come. 22 And he put all things under his feet and gave him as head over all things to the church. Ephesians 1:19-22 ESV