Telkom doesn't care for their existing customers

I went to upgrade one of my contracts (I have 8 with Telkom) on the 23.09.2017. After hours of waiting they informed me that I must pay 25% deposit on my new contract device!!! Why???? Now all of a sudden some of my accounts are in arrears, which isn't the case. I need someone from Telkom to phone me and tell me why do I get treated this way?? Must I cancel ALL my contracts with you and rather go to another service provider. I will be more than happy to take my business to someone who really wants it. I need answers today