hibiscus is inside and leaves are turning yellow
What am I doing wrong?
Did you just bring the plant indoors? If so, it's going through a period of shock because the amount of light has been changed radically. You will also need to pay special attention to the watering. This article will help you bring the hibiscus indoors successfully: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/hibiscus-container-care.htm
A few more thoughts on yellow leaves: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/answers-to-what-causes-hibiscus-leaves-turning-yellow.htm