If used alone, the water-locking property of hyaluronic acid itself will absorb the water in your epidermis, which means that the epidermis will dehydrate and form the symptoms of sunburn.
Therefore, the hyaluronic acid stock solution must be mixed. I've been using Sun Club now, and then I use a small watering can filled with emulsion, and then I drop two drops of hyaluronic acid, so it's not tight and it's starting to work. Instead, it is used in this way, and the skin that has fallen off excessively some time ago immediately recovers its elasticity.
So, change the usage!
Never use it alone!