Lies,no customer service and don't care atitude

Good day please assist on the 14/12/21 l bought grocery up too R1200 and was issued with the invoice for Bata shoes.The cashier Charmaine Muzerengi advised that l can come and claim the voucher anytime before exp Jan 2022.So today l went to Spar at the Square in Boksburg and they refused to assist me as this was meant to be claimed on the same day even the store manager was not willing to assist and also gave me a cold shoulder and said they is nothing he can do.