Making payments directly to card company and not Zwicker

Zwicker. On my credit report it only shows the one month two years ago where I was late with payment and that is because the DSC took my money but didn't make payment. As soon as I figured it out I started making payments immediately to my online account with Discover. Again I only have that one late payment from two years ago. Otherwise I have been paying on time with Discover's online account service. I have spoken with the non-attorney hired by Zwicker and explained to them I am making payments, but they still call and send letters. Even though I am not sending payments directly to Zwicker and have been consistenly sending payments to Discover and have not been late except that one time two years ago. What could honestly happen as far as the court of law at seeing that I am making payments every month, even though not directly to Zwicker? I take responsibility of what I did two years ago and of my bills, but I cannot afford to send them the full amount.