Annoyed

I received notification about my outstanding account about 3 weeks back. I asked call centre staff to email me my invoice so I could have documented record of the debt. I waited a week with no response and figured they would contact me about the silence. A week and a half later, I receive a secondary call to confirm my email and eventually the statement came through. I notified call centre staff that I would make payment t the end of November. Since that call I have been harassed with phone calls and sms's rep early asking me when I will be paying when I had already spoken to staff about this matter. I emailed requesting for the harassing communication to come to an end. I made payment of 250 yesterday and emailed screenshots of the transaction to Mr Michael. I received yet another call today with the lady on the other end badgering me about when I will be paying. This woman then dropped the phone on my ear and a after calling me back she co tied to shout on top of my angered tone without listening to what I was saying to her. She then dropped the phone on me once again. I have never been more aggravated in my life. DISGUSTING SERVICE ?