Bad customer service

I had a bad shopping experience at exact mabopane, on the 27-10-2020 I bought things for 799, so the following day I went for exchange wen I found a rude consultant by the name of Mahlatse, he help me with the exchange but after exchanging my balance was not the same as yesterday, when I asked the consultant he said he doesn't no why, I ask him why you don't know I as a customer how would I no, he said again I don't know, I as a customer I have a right to know what I'm paying for, I can't just pay just for fun, as I am a regular customer i didn't expect that, or mayb TFG they don't train their staff about customer service they just wanna receive our money without treating their customers with respect?