Poorly customer service and unprofessional behaviour

Greetings, so last month i did a laybye at ackermans estcourt took it out within few weeks then yesterday i went to do an exchange then the so called manager was so rude, mean and unprofessional, went to one of the cashiers told her i want to do an exchange, called an override the manager came and asked where is the slip i told her that i don't have it anymore but will it be an issue since it was a lay bye she can be able to check it on the system the mananger refused to do an exchange for me shouting and yelling at me INFRONT of her stuff members and customers that were available at that time that she won't override for something she doesn't know, accused me of *****ing, that how will she know that i bought those things, i told her to check the lay bye on the system it will show she refused. Is that how you treat your customers? 1.Poorly customer sevice 2.Unproffesional behaviour 3.discriminatory of their reputation infront of staff members and customers If no major actions are not taken by the unprofesional behaviour from your manager or im unsatisfied, i will escalate the matter to the next department or even take legal action.