Complaint

I have a data simcard that I have never used since February this year. There's a lady from Mondo who called me and pitched a sale indirectly. Now I had to make a monthly payment of R100 from Feb/Mar for the simcard. There was no service on the network so I tried to call their customer care line which is not toll free and I am unemployed and vulnerable. They do not pick up for the past 2months till I run out of airtime and I live with pensioners no way to keep on buying airtime. Long story short, this morning I received an email from them saying I need to pay R2k+ on my account with them. I don't know where does this money come from as I know of R100 monthly either way they did not respond to me when I wanted help. I've never used their simcard for data at all not even once as it does not have network. I am so devastated, frustrated, ambushed, and all that. How can I be treated like this, I am breastfeeding my infant I do not have time to stress.