Dear Friend, There are various causes of genital rash. These range from infections - parasitic, fungal, viral like herpes - autoimmune conditions, contact dermatitis or allergy. Certain creams or materials of the innerwear can be responsible for allergic rashes. You have already tried ringuard, but no results. It is advisable that you connect with medical practitioner to ascertain the actual cause. The treatment will depend on the diagnosis. It can vary from fungal to bacterial ointments, pertaining to the cause. -Varad Clinic (Pune)

Change your innerwear first. Maintain good hygiene. Clean it up nicely with warm water and soft cloth. However 12 14 days is a long time so what you need to do is go visit a dermatologist or a physician show the rashes to them and with proper examination and tests they'll be able to diagnose the condition and provide proper treatment for the same.