Hi,
Welcome to ehealthforum,
It is difficult to comment on the vulval lump that you describe without examining it. If has been persistent, you should consider getting it examined by your doctor/gynecologist to look for the underlying cause. Treatment as appropriate (based on examination findings and investigations results) would be started to help you. Be in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately. Drink plenty of water. Take adequate rest. Maintain healthy diet and lifestyle. If infective cause is detected, and if you are sexually active, get your partner also treated simultaneously to prevent chances of re-infection, and avoid having intercourse while being on treatment.
Take care.