Hello. Thanks for writing to us at healthcaremagic I would suggest that you discontinue with the use of sunscreens altogether, as of now, since sunscreens can cause acne, specially since you have oily and acne prone skin. It is important to restrict the use of cosmetics to the minimum, including sunscreens and moisturizers. Regarding acne treatment, I would like to mention that Isotretinoin can be restarted and just 20 days is too short for it to produce any significant improvement in your acne. In addition to Isotretinoin, you may topical retinoid e.g Adapalene gel for comedonal acne, once daily at night. Topical retinoids are comedolytic and therefore also prevent new comedones. Since you seem to have sensitive skin therefore you may use a gentle cleanser for face wash e.g cetaphil cleansing lotion, twice daily. Regards