HELP HELP HELP 🙏🏼🙏🏼🙏🏼🙏🏼

A couple of months ago I got this rub mark and it's really itchy.   tried everything to get rid of it. I assumed it was just from my bra rubbing. I switched to no underwire. I don't wear a bra when I don't have too. Creams. Breathable clothes and keep it clean but it seems to be getting bigger. Has anyone else had this? Anything would help. I'm inbetween insurances and don't want to go to the er for a rub mark.