R500 Honor Pick n Pay voucher

Signed up for an upgrade on the Honor promotion on the 5th of July, was advised to claim for a R500 Pick n Pay voucher, to date no voucher, I have been back n forth with MTN but they keep referring me to the rep I signed with or the Honor rep ,MTN refuses to accept responsibility for the non issue of the voucher but MTN is actively advertising this R500 voucher but when you enquire you told take it up with Honor but we sign a contract with MTN not Honor