Shoppers Drug Mart complaint: A Simple Request

I walked up to the cash register to request a reprint of my receipt since it has gone on sale since I purchased it a week ago. The associate, Kayla (or so she told me after hiding her nametag), was for some reason very adamant about my mother and me using the self-checkout when I had already told her I just needed a receipt to be reprinted for a valid price match against their own sale. She slowed her speech and increased her volume as if to suggest that I did not understand what she was saying to me. A simple request to get the difference back that I am well within my rights for escalated to a big fit with attitude in front of a full store. They then said they do not do price adjustments, yet I have had them done at other stores by purchasing at the discounted price and then returning the higher-priced item on the corresponding receipt. I, being in customer service as well, suggested that we proceed as such since I waited in line already – both Kalya and her manager Scott saw this as an impossible and preposterous idea. When I insisted on getting my receipt reprinted as I had initially requested, Kayla made a scene of it – forcefully ripping paper to use to write, slamming the paper down, snatching a pen with aggression, taking my phone from me to get my PC optimum card number, and on top of it all she mumbled things under her mask but I could make out a few words like ridiculous and fing annoying. Not the type of customer service we need in these trying times. She finally got my receipt in a matter of 2 minutes, which is all it would have taken if she had not made it such an issue in her day to stop and listen to a customer’s normal request.