Vodacom Unable to Provide Copy Of Tax Invoice

Our compant purchased airtime for a staff member in November. There was an issue with bundle allocation, which was eventually sorted out. We have been trying to obtain the supporting tax invoice relating to the airtime purchase, for the past month. I called Vodacom today & no one is able to provide me with a copy of the invoice. The order history option does not work via the login. I require the tax invoice for VAT purposes. Please can someone get in touch with me as soon as possible. Vodacom is such a large organization, I find it unbelievable & unacceptable that someone is unable to send me a copy of an invoice. We purchase airtime & data for staff on a regular basis & we get the invoices instantaneously. I don't understand, why this is any different. I urgently await your response.