Prank call from a store

This morning I received a call from the number ********** . When I answered, I heard a lot of background noise, as if it were from a retail environment. the lady phoning me started laughing and then asked to speak to me, using my Legal name, a name I do not give to random people. After I confirmed I am the person she was looking for, the lady laughed, said "yeeeeaaaaah" and then dropped the phone in my ear. Out of all the 10 times I tried to phone back, the call got rejected after a few seconds. I then traced the number to find out that it belongs to the Foschini group in Somerset West. I recently had a TFG card opened for me without even being asked, when I bought something from Sterns. The lady merely asked for my ID number, phone number, and name/surname before I paid. I assume it is because of this that my number would be available to whichever employee decided to prank call me. I find it absolutely shocking and childish that any company would allow such unprofessional and childish behavior from its employees.