Bad service from Shoprite Florida

I went to Shoprite Florida over the weekend with a R4000 E Gift voucher that i have received. They told me to come back the next week as they need to sort the voucher out. It apparently only shows R100 discount, they never contacted me back to tell me what is happening. This really is terrible service and up until today I am still waiting for my voucher to be sorted out. This service really is unacceptable