I have acne prone oily screen. currently i am using lotus spf 50 suncreen. usually i apply sunscreen 20 min.before leaving my home... let say at 8 am in morning. and i get back to home after 8 in evening. and i usually dont use outside water on my face. so i dont wash it inbetween the working hours... but i read that, sunscreem should reapply every 2 hours. so plz someone tell me, how can i reapply my screen. do i need to wash my face? and also tell me the good sunscreem for oily face...that will not clog the pores...also will not give me that oily effect...