terrible service

i received a voucher on the 19th of May which is my birthday the vouchers was to expire on the 31st of May,on Saturday i went to Edgars Birch Acres Mall and i was told i cant use the voucher as the system has been off line since the lockdown but what i don't understand is that the voucher was sent during lockdown and no further explanation was given but my biggest problem was the attitude.What i decided to do was to close my account because they did not seem to care,i expected the lady that was assisting me to call the Manager but it never happened i think going forward this store will close if Edcon does not take action as i have had a bad experience previously in the same store more customers will close their accounts if they get the same kind of treatment i got.