Removing sweat stain polyester

Hi!

Anyone have any hacks/solutions to get this sweat/ water stain off 100% polyester! I took it to the dry cleaners two months ago and after a month I looked at it and saw this was on my BUTT. I was like ugh because I went through so much to even get this jumpsuit & need it for brothers rehearsal dinner Friday! (Side note: had it dry cleaned visiting long distance bf after a family wedding so he had to pick it up when I went home, hence the long gap of time)