Its pitryiasis capitis or sebborheic dermatitits along with sebborrhea(oilyness).
It require maintaince like daily shampoo (mild hair cleanser like hair 4 u shampoo) every altertnative days scalp lotion like ketaconazole & salicylic combination or sulphur, zpto...etc. Allow it act for minimum 3-5mins on the wet scalp &wash it off for 4-6 weeks after that maintain weekly once.
Its all to be maintain its chronic problem depends on the local hygiene, harmonal activity, stress...etc.
Next Steps
Dont use hair oil since it increases...just check any zn (zinc)defenciency...improve your diet with shampoos as i explained .
Health Tips
consult dermatologist for further treatment & clarifications.