City of Tshwane doesn't care about customers

They refused to make an arrangement for me because I didn't contact them within 7 after making the 30% payment of the debt. No one told me I must make an arrangement within 7 days after making a payment. Now they want a further 30% payment of the.debt. I sent an email to customer care and was never informed about 7 days, and never received a response to another one sent to credit control Why are they making it difficult for customers to settle the debt. I wanted to make an arrangement and change to prepaid