Dunkin'

I tried to place an online order through the app but it wasn't working. So I went inside and ordered the same order at the register. I place my order and go to the pick up line. As I'm standing in the pickup like she calls my name for a online order. I tell her that's impossible since I never got a confirmation that my order when thought on the app and show her my phone. She then screams at my and tells me I'm lying. I had to spend $25 since the same order was placed twice and she refused to give me a refund. She hadn't even started making the order I placed at the register but refused to give me a refund.