Question regarding the effects of high-frequency beauty devices that are said to improve skin elasticity

As we age, skin elasticity decreases. When we are young, even if we only apply toner...

I used to maintain my skin's elasticity, but now it seems I can't do it without the help of a device.

With the advent of the "100-year lifespan era" and the increasing social activity of the elderly, the desire to improve sagging skin is natural. That is why I started considering high-frequency devices among beauty devices.

How long is the shelf life after high-frequency treatment? What is the appropriate treatment cycle? What is the most suitable device? As a beginner, I have tons of questions.