Paying for a service I did not use

I used this service once in the first month I joined.

Guys, Edge handed me over for a service I didn't even use. R12 000? they requesting this money from me during these times. for 3 years I haven't gotten any communication from them and now they hit my with a R12 000 bill for a service I didn't even use.

I have a baby, this is something i definitely cannot afford. How can to ask a minimum wage individual who is supporting her family to pay for a service she didn't even use?

This is not right guys. I didn't go, I didn't pay because I had lost my job. Now that I'm finding my feet Edge is all of a sudden making contact after 3 years of no communication about my gym contract. I just don't understand.