AGAIN A PHONE CALL

Sylvia Called me once again stating this is MRS DAVIS, just a reminder to pay your STB account. I said um ok, she said not um when are you paying? This lady thinks she is GOD!!!! I Said to her I paid it yesterday 25/02/2015. I am paying but still I get these phone calls. My problem is I get smsed on a day before payday, then I get a sms on pay day. Then on payday they phone me. Two days later they phone or sms me again. Up until the day the payment reflects they keep on bothering me. I work with customers and its so embarrassing if they phone you for money. PLEASE HELP!!!!