How do I get rid of cellulite in my armpit area?

I notice there’s somekind of fatty deposit (I really don’t know what to call it) by my armpit…the fold at my armpit. I know females commonly have something like this, but mine seems to be more obvious (I’m 5′1″, 105 lbs). I’m not overweight and have been doing lots of weight training at the gym for a couple months…seems it is not going away at all…or is it possible to get rid of it?

I know there are those “cellulite massage treatments”…but for some reason I don’t believe in such “miracle” cures that I have to pay a fortune for.

If you got any ideas, pls share? thank u!