Not getting information asked

Struggling with Vodacom. We could always downloaded our statements, Tax Invoices and Itemised Billing ourselfs on the Vodacom platform. Since Jan'16, we can't anymore. We phoned in many times, they will send our statements and Tax Invoices with our Itemised Billing in \Excell\" format, but we still do not get the information. My father send a letter to Vodacom giving me authorization to operate on his account, they responded back, but every time we phone in, they don't see the letter on their side. When my father phone in requesting the information we need, they do not send the correct information! This is really frustrating!!!!! NO ONE in Vodacom is helpfull!!!!! What are they there for? When will the platform been sorted out? They know about the problem for 3 months now, but do NOTHING about it!"