Vodapay sells vouchers that dont work

I purchased vouchers from Vodapay, one of which did not work at the merchant, Steers. I checked with Vodapay and they confirmed that one did not go through and they will follow up with Steers. Steers contacted me and checked back with Vodapay, whereafter Steers came back to me and advised that Vodapay claimed that the vouchers were redeemed. I went back to Vodapay and am still awaiting their resolution. I have another voucher for another merchant that was purchased on Vodapay that did not go through, but now it cannot be used. This is a lot of money and we need them to resolve it, but they wont.