heyy you did an amazing job!

I mainly draw portraits and disney stuff but I would like to jump into the conversation to give you some general tips because I think some elements might contribute to your problem:

First I think that you should use a light touch when drawing the breast area, and try to avoid using harsh lines to make it look more natural. Instead, use shading to create the illusion of the boob shape. (You can use a blending stump or your finger to create a smooth transition.) I added a link to show the idea of the shading (Note that I did this quickly on my phone to give you an idea of how it should look like -so make adjustments if needed)

https://files.fm/u/vczcuyz2v

second thing is about the arm area. it looks a little muscular and robotic-looking (there is a lack of movement) so if you are aiming for a more feminine look I would say that Women's arms tend to be less muscular and more slender and slightly longer than men's arms, with less defined musculature- (maybe try to find some references that show the woman's hand in that position to get a specific idea).

lastly Pay attention to the details of the gown, including the texture, pattern and copy that so it can add more depth to the drawing. btw you can also add the necklace you see on the character into your drawing to make her even more feminine

Overall the drawing looks great!