dc debt review

i would like to get assistance regarding DC DEBT Review, i did gave them my information for them to assist me in paying my debts.... but before 24 hrs i sent a cancellation letter ( according to their therm an condition to cancellation within 24 hrs)..for which they did receive the letter ... now they blocked my name and all my accounts... i did pay my accounts if full, without their assistance .. DC debt review wants me to pay r1500 ... for which i dont understand please help