Compare your work with current Stock inventory to see what gets accepted. Keep in mind that Stock already has 30 million perfect flowers in every possible size, shape & color. It's unlikely anyone will see, much less buy your flowers. There's too much competition in this keyword. Find other subjects that have less representation.
That said, your photos contain the following technical problems:
Adobe Stock customers expect the highest visual and technical quality for use in commercial projects. See these links from your Contributor User Guide for more tips.
Also, keep in mind that Adobe Stock is an image storage platform designed primarily for business needs. This means that most of the images available on Adobe Stock are intended for use in professional projects.
This can guide you in your choice of photos.
What's wrong - well, as mentioned, the photos are underexposed - that's a big problem.
You need to learn about the histogram in digital photography; it can be helpful to tell about the exposure of your image. Also, your composition needs work.
Read these links:
You have not achieved sharp focus in either image, and the second one is significantly underexposed. Additionally, Adobe already has millions of floral images, and doesn't need any more, unless yours is a very rare species.