I was in your situation before. I had always had double eyelids, but unknowingly the other eye became double eyelids. Later, I got a girlfriend. She used her nails to draw lines on my eyelids and said that if she drew lines frequently, I would have double eyes. My personal experience is that I would do it a few times every morning and night when I went to bed, and also when I had nothing to do. It took about two months. If I kept repeating it every day, my upper eyelids would become tighter and they would recover. It’s double eyelids.

If it helps you, please accept it, thank you!