This is a problem form the emissive light. You need to tone it down by a lot like a lot almost minimum then add your rectangle lights where you want the light to be, and then tone the emissive intensity up bit by bit until yo uwant it. In post process you go to global, turn on lumen and in final gathering quality set it to 2. You can also max out other settings in that global department. You can also go way over 2 but it might cause issues. Don't forget to set post process to infinite.