Thank you for your question and pictures. African violets are one of the most popular houseplants and produce beautiful flowers because they are usually easy to care for. I'm not sure what type of light you have, but a lack of light will produce a "leggy" plant as shown in your pictures. Also, if they violet is older, it will grow the way you show in the pictures. I would suggest re-potting your violet and bury the stem up to where the leaves start and that should take care of your problem. Here is some information from Extension on the care and soil mix for African violets:

https://extension.umn.edu/houseplants/african-violets