Incorrect Data Billing

Company has had a corporate account with Vodacom for more than 15 years & never had an excessive data bill on any of the contracts. At the end of January at 5am on a Sat morning one of our senior managers' cell phone data was hacked & over 11GB of data was downloaded from the app store in one session. This resulted in a R14000 data bill even though the contract had a R3000 call limit loaded. The manager woke up to 3 consecutive SMSs stating that he had used 50%, then 75% of the call limit; & a final SMS stating that he has been softlocked. On Saturday morning the owner of the company went into Vodacom to investigate the issue & was informed of the download that had just occurred. Vodacom's consultant informed us that they are aware of data theft. They reported it & informed us that the amount would be credited. On following up the query we were informed that they would not be crediting the data bill & that the company was liable for the data charges. This is not acceptable as we know for a fact that it was data theft as no additional apps were added top the phone at that time and that the company should only be liable up to the R3000 call limit if anything.