I used to have this problem when younger but found Mitchum very effective - it was a godsend. I think it’s still available. Ordinary anti-perspirants were frankly useless.
It'd be a bonus if I broke out in a sweat as right now I'm perishing cold. The sun shining in the back kitchen is no good to me when I'm in the living room, it's wasted out there.
If it happens even though you use an antiperspirant, I think you should take medical advice. My understanding is that most people perspire far less as they age.
Being 75 and still sweat under my arms big damp patches it happens when I dress to go out for meals, walking , shopping stops when i am just sitting at home ! no health issues slim and very active, friends same age can’t help but remark on it as they don’t perspire at all !