Bad customer service from Steers

I am very unhappy with the customer service received from Steers. I had purchased 3 Steers vouchers, via the Pick & Pay App on 07/11/2020. I tried to redeem the vouchers and was told, that they were invalid. After numerous calls back and forth, I was promised that it would be sorted out. Until today, nobody has gotten back to me to let me know, what's happening! I've requested that the points deducted from Pick & Pay be credited back to my account, but this has still not been done either! Empty promises made by Roché to get back to me regarding this matter is unacceptable!