Shoppers Drug Mart complaint: Customer service

I bought butter, PAID for it with my debit and as I was done my receipt won’t print for some computer reason so a girl tried to reboot and help me but couldn’t figure it out. A supervisor named Brandon apologized for the inconvenience and I understand things happened and I was upset but wasn’t by any means rude. Then he calls this other sup named KIM and she said you can’t have a receipt but I can try and find it in the back and I said ok, came back and said she couldn’t find it and that it didn’t go thru so I DIDNT PAY FOR IT. I said I did, it came out of my debit, she said no it didn’t go thru. For a supervisor, Kim needs a better lesson regarding customer service. I worked in customer service and I know that things out of control happens sometimes but telling a customer didn’t pay for something when I’m fact I was there, the other girl working saw the transaction go thru but the receipt won’t print is beyond me. That’s why I waited to get a receipt cause I needed a proof of purchase. Maybe retrain your employees in how to properly deal with stressful environment. I attached a pic and you can see shoppers drug mart.