Nashua to Vodacom - incorrect contract details

When we were automatically migrated from Nashua to Vodacom, one of our two data contracts (both 2GIG, both renewed at the same date) was incorrectly captured as 1GIG instead of 2GIG. Vodacom is insisting that this is the info that they were given, even though I have emailed copies of the last Nashua invoices that show that we were billed for 2 GIG. Customer Service recommended I contact Nashua to rectify it. Obviously the number that was given to me is not manned so I'm not sure what to do next. I don't understand why they will not change it back to a 2GIG. I am not prepared to complete a new contract application as the existing contract is from Feb 2014 for 24 months.<br> I'm hoping that Vodacom will just change it to 2GIG (as it was previously)and bill accordingly<br>