I was just given a Hibiscus and I repotted it into a bigger container. Every other day I am finding leaves yellowing and I don't know if I am doing something wrong. The plant sits in full sun from mid morning through mid afternoon.
Why Are My Hibiscus Leaves Turning Yellow?
Here's an article that proposes several possible answers for your problem: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/answers-to-what-causes-hibiscus-leaves-turning-yellow.htm
When you say you repotted it into a bigger container, there's a possibility that the new container is too big. When up-potting plants, you should always go just one size up, i.e. 6" - 8", 8" - 10", etc. Planting into a pot that's too large generally results in the soil, and consequently the roots, staying too wet.