Incredibly disappointed!

Very disappointed with the way I (a paying customer) has been treated by the area manager from Roodepoort. The area manager called and told me that she would leave a voucher for the value of my meal (R244) at Nandos Allens Nek (Roodebasin) Roodepoort. We went on Friday to pick up the voucher at Nandos Allens Nek (Roodebasin). The manager on duty was very helpful. The voucher that was left at the store was only for R100 not the R244 which the area manager told me she would leave at the store. Is this the way Nandos allows a paying customer to be treated after receiving such a terrible meal and service?