Bad Customer Service U-Save Bethanie

Needed a purchase and a cash back, Supervisor on the floor (Jabu) who refused to give me a Surname instructs the teller not to service me, I request a store Manager [(Sello) who also refused to give a surname,] came and as a customer I told him my complain, I have a card I need to purchase and cash back Jabu instructed the teller not to serve me. Jabu explains why to Sello, I then said to Sello as explained my mother received a **** money from this yard I fixed that yesterday(Full story), now he knows the story! and I specified now answer me on my Question I have a card I need to swipe and do cash back, Jabu decides to abuse power. Sello did not answer me, I told him about Hello Peter, he said I must not threaten him. When he took the job he said he will able to deal with customers complain, my Mother if over 70 years a pensioner I had to step in, now with me when I receive such bad services from both the supervisor and the Store manager it makes me think, should we make more anonymous shopping to check the level customer service from management in this store, Bethanie Shoprite U-save. I need to understand why Sello could not deal with a customer’s query which was in connection with his employee? Are they both fit for the Job?