Bad Service Bad Attitude

I bought a Lindt bunny of R99.00 at Pick n Pay Tyger Valley on Saturday 24 March 2018. I wanted to engrave the ribbon, but the ladies was not in the store, I was told i can go to the actual Lindt store to get it engraved. I went there and the lady said they don't have the machine yet, but i can go to any Lindt store as long as i keep my receipt. Today i went to the Lindt store in Canal Walk, I asked the gentlemen if they have the machine and he said yes and i explained to him, he then went to check with the Manager Marco who blatantly said NO they can't do it unless i bought the Lindt bunny at their store. So i would like someone to answer me, how come your Lindt shop in Tyger Valley was willing to do it and not your Canal Walk store, it is one shop after all, or am I missing something here.