Lighter armpits?

Hi ladies, Im in need of your help. Ive been trying to whiten my armpits for a while because they are so dark but nothing works. Ive been waxing for about a year. I’ve tried turmeric, lime (i know its bad thats why i stopped), baking soda, you name it but nothing has worked.

So Im just about ready to go to the dermatologist for help but I wanted to see if there was anything else i could try before going for a visit. Ty