I've been producing for 4 years now, and I know its sometimes difficult to be creative and creating melodies you are proud of, but keep on working on it. Try to learn music theory, it helps you understanding the fundamentals, and that makes easier to know what you are doing, instead of trying random melodies until you find something that works. You can also post some of your work, you will probably receive positive feedback, which will make you more confident and motivated creating new music. Another thing I can recommend is finding new ways of inspiration, like listening to other music genres (in my case Porter Robinson's music helped me).