From my perspective, you should check your blood with a doctor - make sure your thyroid and testosterone are normal. I would assume you are not on any recreational medications etc.
One treatment can be localised botulinum toxin into the armpits or palms area which is the most socially troublesome/problematic regions. However, it doesn't work for the back.
This treatment also has to be done regularly, and it works by intercepting nerve messages on sweat secretion.
Sadly, it isn't technically natural nor permanent.
Another treatment which can be done is to utilise microwaves. See Mira-dry
https://www.sweathelp.org/hyperhidrosis-treatments/miradry.html
