Struggling With Debt and Need Advi

Hello there,
I’m 25 years old and have been struggling with debt for quite some time. I currently have around $15,000 in credit card debt, and honestly, I don’t know how I’m supposed to pay it off.
I’m currently working two jobs, but due to the job market where I live (Puerto Rico), I’m lucky if I even get 12 hours of work a week. Right now I’m making $10.50 an hour, and I’m barely staying afloat.
I’ve never missed a credit card payment, but the situation has gotten so bad that even though I make all my minimum payments (which is all I can afford), I never seem to make any real progress on the debt. Most of what I pay just goes toward interest.
I’ve called all five of my credit card companies to ask for an interest rate reduction, but only one was willing to help. I also looked into National Debt Relief, but after doing more research, I decided it wasn’t the right option for me.I’ve also tried selling most of the things I own, but the market here is pretty slow and I haven’t had much luck. At this point, I’m open to any suggestions. I really need help and would appreciate any advice from people who have been in a similar situation.
Thank you.