Poor contract cancellation process

Few weeks ago I made a contract cancellation and i was informed it is being processed and I will get a call from telkom when the process is done. I never got a call so I called to find out and the person I spoke to said it is being processed and they can see a settlement amount of about R1300 but I must wait for someone to call and confirm everything. Two week I get an SMS to say my contract is now prepaid. Today I get an invoice with a DEVICE CARRYOVER/OBLIGATION of R400 which I fail to understand as no one called to explain what needs to be settled before this contract can be made prepaid and whether I agree to the settlement amount or not. To make matters worse I was paying R199 for the contract and its got 4 months left and now they pulling stunts like this. This is very poor and with the other two contracts left I wonder if its worth carrying on doing business with you or should I take it to another provider when they expire. Sort this mess for me please !!!!!!