Bad service

I was at Markham Zevenwacht Mall Cape Town .. wanted to buy 2 shirts but couldn't receive the discount because apparently they couldn't register my ID (Rewards) or it gave them an error message. My mom who was with me never carries her ID on her. What shocked me was that the S/C told me to ask anyone else in the store (customer) for their ID number which I refused. I asked her to call customer service to find out why I can't get my discount or even a rewards card. Unfortunately they couldn't do anything about it and the S/C even walked away from the counter while on the phone with them. Apparently it was up to the Store manager to authorize or something but the manager didn't even had the decency to come and explain to me what's happening. Apparently she was having a meeting with a staff member(on a busy Saturday morning). I worked for TFG for 11 years... I left Almost 10 years ago for better prospects ... And their explanation was that it's maybe because I was "Staff" that is why I don't qualify ... Which really sounded like the biggest joke to me....I left with only 1 shirt because I unfortunately needed it. If there is someone that is interested in rectifying this problem before I escalate it they can reply to this message URGENTLY.