I'm so sorry to hear of your discomfort. To assist you with your question, I need a little more information- Have you noticed any discharge through belly button?- Do you have associated pain or swelling?- Do you have any other medical issue?- How long has this been going on for?
Thanks for providing the additional information.
Usually such discharge along with itching is caused by a fungal or bacterial infection.
Also most belly button discharges is almost a fungal/ yeast infection.
Firstly you should clean the area by gently turning it inside out or using a q tip with soap and water or hydrogen peroxide. Then you need to use anti-fungal treatment (like the ones for athlete's foot) for eg. Tinactin 2-3 times daily to the belly button.
This will cure the symptoms. If symptoms doesn't improve in next 3 days with above tips, then it can be bacterial infection, and you may need prescription antibiotics.