Differin ointment

This is Differin ointment I bought when I went to Vietnam. It is originally an ointment for acne, but the pharmacist recommended it, saying it is also good for melasma and shrinks pores, and told me to just apply it like a cosmetic product, so I bought it. I used it a few times and then forgot, so it’s still unused~ I need to apply it diligently.