Dandruff is a common situation more common among teenagers. It can be more problematic if you are using hair oils. So consider discontinuation of oils and using an antifungal shampoo everyday for first week and then reduce the application to twice a week for maintenance. You should keep the shampoo at-least for 5 minutes on the scalp for it to act. This should solve your problem. However if problem persists, consult a Dermatologist for proper diagnosis and treatment and to rule out any other skin condition. Hope it helps you.
Your dermatologist will decide a treatment plan for you after a consultation.
Apart from active pharmaceutical medicines, a healthy diet and lifestyle is mandatory to achieve results.
Greetings. The shampoo that you have been prescribed is good for treatment of dandruff. You must use it at least two times in a week and each time you wash your scalp, you must leave it on your scalp for atleast five min to seven min before you wash it off. About the oil - kindly ask the doctor who prescribed the same.