HELP PLEASE: My armpits are gross 😬dark spots/discolouration

It’s gotten worse over time, I’m switching from shaving to waxing from now on. I believe my armpits are just really sensitive, I haven’t seen a dermatologist yet but I’m not sure what help they will do?? I’m always self conscious about exposing my armpits when I’m wearing something sleeveless (in public) and I don’t know what to do. I’ve been using an antibacterial lotion (Isocol) and a toner for clear skin (Witch hazel) on my armpits every day after I shower. I haven’t seen a difference yet, I tried using lightening creams but I think they’re the ones that made it worse.

I would really appreciate some recommendations please of products or home remedies that actually work!! 😬 thank you.