No Invoices, account paid and still suspended

Today my phone lines were suspended<br> Since August 2014 I have received 1 invoice from Telkom, for Oct 2014 and this was delivered on 2015-03-15. Contacting them regarding the matter is impossible as they always have high call volumes and holding on for half an hour to and hour is not an option. My usual monthly account is between R1,300.00 & R1,600.00. So I have been blindly paying Oct 2014-R1,600.00, Nov 2014-R1,400.00, Dec 2014-R3,000.00 (double for Dec & Jan), Feb 2015-R1,700.00, March 2015-R1,600.00. I received a call from Telkom earlier the month telling me that my account is in arrears by around R300.00. I explained to the gentleman that I have not been receiving invoices and asked for it to be sent via e-mail so that I can resolve this account. Needless to say this has never happened. This morning 2015-04-01 all my line were suspended due to non payment. What exactly do you (TELKOM) want from me? Should I do all your accounting for you as well? How do you expect me to pay the exact amount when you make no attempt to send me invoices? I have tried my utmost best to keep this account paid on time without any help from you. Yet you have the nerve to suspend my lines